We Recommend Uploading Files sRGB If Uploaded In CMYK They Will Loose Vibrancy When Printed.
PNG,PDF, only with Transparent Background
We Do Not Recommend Any Artwork With Super Tiny Details That Are Below The 9PT Mark it will NOT get Unsderbased And it Will Most Likely Not Get Transferred Correctly Onto The Garment/Fabric (How to fix the issue) Simply add a stroke to your design to make the tiny details a bit thicker before submitting the artwork for printing. below is a picture showing the issue.
Transparent or translucent gradient IS NOT recommended, it will lose it “blending” effect where transparency of 30-40% will start to break and create jaggy edges in your artwork because the printer will lay white under them thinking there is color there creating an effect like the one below.(How to fix the issue) Make the gradient more solid or remove it completely from the design.
Check your artwork edge quality and make sure they are sharp enough and does NOT contain “dirty” colors resulted from badly removed background process. How to check the quality of the edges simply zoom in at 100% and if it looks like the image on the top the output will be like the image on the bottom.(How to fix the issue) You will need a higher resolution image or get the design vectorized by a designer.