For Auto-Punch, turn on the pre-roll feature and set it for 2 bars(or whatever you want), highlight the region you want to record, or just place the cursor where you want recording to start(if you want it to just continue till you hit STOP. And hit record. Search youtube for some tutorials on this or almost anything you want to learn as there's a good chance someone has posted instructions
. Above all, remember your best friend......Ctrl=Z(when it all goes bad, UNDO)