How to make your own Picrew image maker 

Beginning - how to start the Picrew
3:08 - explanation of terms (what parts, items, and colors correspond to in the image maker)
4:40 - navigating the site (where parts, items, and settings are, what is in each)
7:43 - how to make a part and sort them (the meat of the tutorial begins here)
11:02 - how to add items (and more about items)
14:09 - how to add colors and how to link up colors from different parts
Some things I forgot to mention: The size for the actual images used is 600 x 600 pixels. The size for the icons is 96 x 96 pixels. The site will resize your images if they are not these sizes, but if you want them to be as clear as possible, upload them as this size.
I used one big MediBang Paint file for all of my images (in layers so I could see how they sit ontop of each other) and then I would hide unrelated layers so I could save a png of each item color. The clipping setting on layers is really nice for making different colors of the same item.