A T-shirt is the simplest design to create but fairly basic. Roblox utilizes images in .png, .jpg ... download it to your computer. For each template, notice that the parts are "folded ...

Image format .png, .jpg, .tga, or .bmp can be uploaded to Roblox. The next step is ... Now it's time to create an image for the shirt. Open the template in any image editor; some free options ...

Roblox is a ... image file should be in PNG format and have a resolution of 512x512 pixels. Enter a name and description for your shirt. Choose the appropriate shirt template from the drop-down ...

so you'll need to design a t-shirt in an image and then upload it to Roblox. From there, just select it to wear and you're sorted! You'll be best off having a couple of templates for this!