Doing as you're instructed him to do will almost certainly ensure that his amp will only turn on when his head unit is in tuner mode and then back off when the source is switched to CD mode or AUX if that mode is present.
The power antenna activation lead is intended for power antenna activation when in tuner mode and nothing else. //content.invisioncic.com/y282845/emoticons/fyi.gif.9f1f679348da7204ce960cfc74bca8e0.gif
To the terminal marked power you will connect the cable that provides 12v+ power to the amp (preferably sourced directly from the battery)
To the terminal marked ground you will connect a grounding cable. The other end of said grounding cable needs to be connected to bare metal somewhere directly connected to the chassis for best results.
The terminal marked remote needs to have a lead attached which originates from the remote accessory activation output on your head unit. Barring that it can be connected to any fuse in your fusebox that is only "live" when the car's ignition is on. This will keep the amp from being on constantly and consequently draining your battery overnight.
The connections marked channels I will assume are your inputs and this is where the RCA cables connected to the preamp outputs on your head unit need to be connected.
Hopefully I have been of some help here.