I painted out a lovely triad with DS yellow ochre, DS cerulean chromium and Sharlie's Pinkcolor deep - a gorgeous colour somewhere between Potter's Pink and Indian red - either of which could equally be used in an earthy primary wheel like this. I posted it on Instagram (Janeblundellart) but I wanted to give a little more information here.
Making my own watercolours, like making my own sketchbooks, is something I have chosen not to do. I want to spend time sketching in the books or painting with the watercolours! However I really admire those who go through the effort of making their own. Sharlie's rewet and painted out very nicely, unlike some others I have tested.
She has an Etsy shop called biscuitswatercolor, where she sells half pans of handmade watercolour. I don't have an Etsy account so can't post a link. I believe she has a number of other colours besides these :-)