First, you must pick your colors
To do so, use this site and find the color you want
Once you got it, copy the HEX number (which you'll find below)
Create an artwork image of that color;
Use any design software (photoshop if you can or canva.com)
Create an image of 3000 X 2000 pixels at whichever resolution (72 will be fine. You can read this article to know why the resolution is actually irrelevant for printing. The number of pixels is what matters) and fill it with your selected color
Save as jpg or png image (ex: Turquoise.jpg)
Create a product design with that color as the artwork;
From your Artist's Portal, click on "Request New Designs" from the right-hand of the Products section;
In the Art section, click on "+" to upload an artwork;
Choose your new color file as the artwork;
Select the silhouettes you'd like designed;
Add styles to request & Send to design!
In max 2 business days, you'll be notified that new designs were added to your Portal!