I dont know to be honest. I use any sound, even vibrate works for me. Doesn't make a difference in my case.
Should I change my alarm clock song everyday or keep it the same (what will make me more likely to wake up instead of hitting snooze)?
That really depends on you. If a sound becomes routine, do you sleep through it? If so then change it often. The best thing to get you up and not hit snoze is to put it somewhere that you actually have to get up and turn it off. It makes harder to just hit snooze and go back to sleep if you are already standing.
Set two alarms one for the time you want to get up, and one for a couple of minutes later....set both of them across the room where you can't reach them from the bed.
