It's a one piece pull knob type. Pull the knob straight back for on and twist left and right for hot/cold.
It's about 25 years old and needs a little work. I *think* it's a Moen, but can't tell because the center cap is missing on the faucet.
I took the handle off with it's single phillips screw. Then there was a white plastic spacer behind that which just came off. Then there was a "C" clip type of retainer that was inserted from the top side that easily pulled out. From here, I'm stuck. I have yanked on this thing to no end and it doesn't budge. There is no corrosion or anything obvious that is still holding this insert in place.
Any tips? I know I'm rather vague on describing the faucet, but it's all I have to go on without pictures.