Designing t-shirts has never been more accessible. Between drag-and-drop platforms, AI-powered tools, and endless inspiration online, launching your own print-on-demand store can feel like something anyone can do (and that’s mostly true). But ease of access doesn’t always mean quality, and that’s where many creators run into problems.
If you’re a one-person team, AI and design tools can absolutely help you do more than you’d be able to on your own. They save time, help you brainstorm, and give you visual results you might not have the skills to create from scratch.
But without a solid understanding of how print-on-demand works, or how to adapt those tools to your goals, you might end up making common mistakes that cost you time, money, or credibility with your customers.
Some of these mistakes come from not knowing how POD platforms operate. Others come from relying too heavily on tools that weren’t built with merch in mind.
Either way, the good news is: most of them are avoidable. Below are seven of the most typical mistakes people make when designing shirts online, especially when they’re just starting out.
1. Using Low-Resolution or Non-Scalable Images
The number one technical issue with online shirt designs is using images that simply aren’t fit for print. People often confuse “looking good on screen” with “ready for production,” but screen resolution is much more forgiving than fabric. An image might appear crisp in a small digital preview and still print out grainy, pixelated, or visibly stretched on a t-shirt.
This is especially common when incorporating images from the internet, screenshots, or even AI-generated illustrations. While AI tools can create beautiful and imaginative artwork, they typically export in raster format, meaning flat pixel-based images like PNGs or JPGs that don’t scale well.
These files might look perfect at the size you generated them in, but if you try to enlarge them for a bigger print area, the lack of resolution becomes obvious.
Unless you’re working with vector graphics (or you’ve taken the time to upscale and vectorize your image), you’ll run into problems with clarity, especially for larger product sizes.
Getting familiar with the difference between vector and raster formats, and understanding how resolution translates to print, can save you a lot of frustration down the line.
Fortunately, there are AI design generators, like Vexels’, which are built specifically with print-on-demand needs in mind. You can upscale your image for print, or even vectorize it, making the design clean, scalable, and editable, which is perfect for high-quality merch.
2. Ignoring the Print Area
Every POD platform has a designated print-safe area for each product. It’s the invisible box where your design is guaranteed to show up as expected. But it’s surprisingly easy to ignore this detail, especially if you’re working in a design tool that doesn’t explicitly show you those boundaries.
Designs placed too close to the edge risk being cut off or misaligned. On the flip side, overly small designs floating in the center of a huge blank shirt can look awkward or underwhelming.
And because every product (t-shirt, hoodie, tote bag, etc.) has its own layout, dimensions, and print specs, what works for one might look strange on another.
That’s why using a tool that adapts to your product is a game changer. In Vexels Designer, for example, you can choose which product you’re designing for and the canvas will automatically adjust to match that product’s print-safe area. You can also set custom dimensions if you’re working with a specific requirement. This makes it easier to respect margins, align your artwork correctly, and ensure that your design will look great on the final product—just like it does in the mockup.
Being precise with your canvas size, and respecting the margins and alignment guides, is key. It’s about avoiding production errors and making sure what your customer sees in the mockup is what they actually get.
3. Overcomplicating the Design
A t-shirt has limited real estate, and the best designs usually understand that. One of the easiest traps to fall into (especially when you have access to endless fonts, colors, graphics, and effects) is trying to do too much at once. You want your shirt to stand out, but piling on visual elements can make it noisy, hard to read, or just confusing.
Text becomes unreadable. Icons clash. Colors vibrate against each other. And instead of one clear idea or message, you end up with a visual mess.
Restraint is often the difference between an amateurish design and a professional-looking one. That doesn’t mean boring, just focused. Choose one idea and build around it.
When in doubt, test your design at different sizes. If it’s not legible or recognizable from a few feet away, it probably needs simplifying.
4. Choosing Colors That Your POD Can’t Reproduce
This is a subtle mistake, but one that can completely derail your final product.
Many people design with color schemes that don’t match what’s actually available on their POD platform.
Maybe you fall in love with a soft sage green background, only to realize your supplier doesn’t offer t-shirts in that color. Or maybe your design relies on a very specific tone of red that looks great on-screen but prints totally differently due to fabric color limitations or dye processes.
This issue becomes even more critical when working with embroidery. Embroidered designs don’t offer full-color printing: you’re working with a limited palette of thread colors, often pre-set by the manufacturer. That dreamy shade might not exist in thread form, and even if it does, the final look might feel flatter or more muted.
The best approach is to always start with the product and color options you know you’ll have access to. That way, your design decisions are informed by the real-world materials they’ll be printed or stitched on.
It’s a lot easier to design something that works within those constraints than to try and fix it later when it doesn’t translate.
5. Using Copyrighted or Pre-Made Graphics
Copyright issues are an obvious risk. Using a branded character, quote, or image you found online without permission can get your store suspended, your design taken down, or even result in legal consequences. But there’s another side to this issue that’s less talked about: uploading generic graphics without personalizing them.
Even if you’re using commercially licensed content, POD platforms may flag your work if it appears identical to designs already circulating.
This happens a lot when sellers use pre-made graphics or templates without any changes. If you and 50 other people upload the same graphic to the same platform, none of you are likely to see much success, and some of you might get penalized.
Customizing your assets is key. That could mean adjusting the layout, changing the illustration or picture, adding text, changing colors, or combining multiple elements to create something new.
6. Using Mockups That Don’t Match the Actual Product
Mockups are essential for showing off your design, but they can also set unrealistic expectations.
Many new sellers use free or generic mockups that look good in isolation but don’t reflect the real product they’re offering.
Maybe the shirt in your mockup has a different fit, neckline, or fabric texture than the one your POD actually prints on. Maybe the mockup shirt is pure white, while the real item comes in a slightly creamier off-white tone.
These small inconsistencies might not seem like a big deal, but they add up, especially if your customer feels they were promised one thing and received another.
If your mockup shows a premium-looking thick cotton tee with structured seams, and your POD ships a softer, thinner retail-style shirt, it could affect customer satisfaction and reviews.
The safest route is to use mockups based on the actual product you’re selling. Many POD platforms offer these natively, and some mockup generators tools include them too. It’s a simple step, but it goes a long way in building trust.
7. Designing Without Your Audience in Mind
Finally, one of the biggest strategic mistakes is forgetting who you’re designing for. Understanding your target audience is key to achieving success in your merch business.
It’s easy to get caught up in what you think looks good, or in chasing what’s trending, without stopping to ask: would my audience actually wear this?
Designing for yourself is important, especially if you want to create a brand that reflects your personality. But when you’re selling shirts online, you’re ultimately designing for someone else, someone who has to like it enough to wear it.
If your design doesn’t resonate with their sense of humor, aesthetic, values, or interests, it doesn’t matter how polished it is.
The best designs often live at the intersection of what excites you and what your audience connects with. That takes research, experimentation, and sometimes failure, but it’s the foundation of creating shirts that people actually buy.
How Can You Avoid These Mistakes?
The truth is, most people don’t make these mistakes because they’re careless: they make them because the tools they’re using weren’t built for merch.
AI tools can generate incredible ideas and even graphics, but they’re usually not optimized for t-shirt printing.
General design tools might help you create something beautiful, but they often ignore the technical and practical realities of print-on-demand platforms.
That’s where a merch-focused design tool can make a real difference.
Vexels Designer was built specifically for t-shirt design and POD sellers. Every feature (from the print-safe canvas sizes, to the use of mockups based on real POD products, to the curated color palettes) was designed with merchandise in mind. When you create a design in the tool, you’re not doing it in a vacuum: you’re designing with production specs already baked in.
It also helps solve many of the issues we’ve covered here. It works with high-resolution, vector-ready graphics that won’t break when scaled. While also gives you the option to scale AI generated graphics or vectorize any image.
Its AI prompts are tailored to merch use, meaning you’ll never get results that include copyrighted characters or overly generic outputs. And you’ll always be working within a layout that reflects real-world production standards.
Bottom line: using a tool built for t-shirt design makes it easier to focus on the creative part, knowing that the technical side has already been accounted for.
Ready to try it for yourself? Check out the Vexels Designer here.