Ive got a CZ 453american 22.

The trigger is ok, but I think it is suppose to have a set trigger. Can anyone tell me how to "set" this thing or if I'm totally off my rocker?

I thought I was getting a 452. Looked at the 452. Got it home and it not the box was a 453. Talked to gun store and was told I could keep what I had if I wanted. Research showed I had gotten a deal so I just kept it. If I can figure the trigger out I'll be even happier.