unfortunately I do not have a tablet, I use pencil and paper in my sketches, I did it in photoshop, here is one of my tuturiales where I show how is my process:
https://steemit.com/artisteem/@inu-jim/artisteem--inu-jim--836815253--artisteem-illustration-art-artzone-digital-art-ntopaz--2018-12-02-22-35-33--artwork--none