Old shower faucet can't find screws

I cannot find any screws to take this off as it is leaking and i wanna upgrade it. Do i twist it off?

 

There should be an Allen screw in the base of the shower handle to take out to remove the handle. After removing the handle there will be an escutcheon piece holding the trim plate in place. You will just trun that piece counter clockwise and it will come off. Then you can remove the trim plate.

 

Theres no screw or allen wrench that i can see

 

Ya your right I don't see one. Hard to tell from the picture, but are you sure there isn't a screw or anything hidding under the hard water build up in the front part of the crease in the handle? This one may be a twist off. Sometimes they are threaded on. I've never seen the particular model you have, but if it has no screw and the handle is one piece which it appears to be. I would assume that the beveled cone between the trim plate and the handle must be threaded. Try to turn it counter clockwise and see if it will unthread. They work like that on a lot of lavatory sink and bath tub faucets. I've never seen that design personally on a shower valve, but from the picture that would be my assumption.

 

I just turned counter clockwise the middle one and it unscrewed.