how do i knit the thumb? 
You follow the directions on the pattern! :roflhard:
The ones I’m currently knitting, you increase between markers over several rows for the gusset, then transfer the thumb stitches to waste yarn. After finishing the top, you come back and pick up the thumb stitches and knit in the round to finish the thumb.
Yep, pick a pattern and follow the directions. Worked for me!
knitbit do you have a pattern you are working on?
Knitbit–
Is your mitten thumb the kind that sticks out to the side? Or the kind that lays flat against the palm?
–Denise