Tips for clean punch-ins punch-outs

Or does it just take a lot of practice? I recorded this guy last night and after he was done with his takes he would say, "i didn't like a couple bars in the bridge/chorus/whatever." I would go back and delete the section as clean as I could and then punch in record and punch out, but I had a lot of trouble getting some of it clean. There weren't big gaps where he wanted to re-record, only like a second where he inhaled, or before an upstroke. So I had to make him re-record an entire section :oops:. I'm using PT 6.4 by the way. Thanks