Hi and welcome to KnittingHelp!
It looks like you're setting up the pattern for one of the fronts. Work 12 sts in the rib pattern that you have been doing and place those sts on a safety pin or scrap yarn for the front band.
Work 11 sts in rib pattern and then increase in the next stitch. This will take 12sts to do one repeat. You can do a knit front and back (
kfb) here if you like. Repeat this 3 more times. So you would: rib 11, kfb, rib 11, kfb, rib 11, kfb, rib 11, kfb.
Rib for the last 7sts. You'll end up with 59sts on the needle.