I'm a heavy sleeper and can't wake up from alarm?

The problem is that IIm a really heavy sleeper. I wake up sometimes after 12 hours of sleep. I use 5 alarms on my iphone spaced like 10 mins apart and still I can't even hear them but when I wake up they are turned off by me and I don even remember that.
Sometimes I do wake up and just don't go out of bed as its cold and I don't wanna take a bath and go to school.
Even when someone comes to wake me up i start making excuses to myself like i feel a bit sick, schools not worth it today etc so that I don wake up and don feel guilty about it.

I need some good tips on how to wake up. And please be in detail with a list of things i can do.
And don't gimme answers like sleep early cause i do.

Put a very loud alarm clock away from your bed. In order to turn it off, you have to get up.

-Decide if you are not waking up since you don't like your day. If that is so, then find something good to reward yourself with, that you can look forward to: Join a club, start a hobby, etc.
-If you have too much homework, then begin doing it with other classmates to make it more interesting. Begin homework earlier.
-If your classes are too hard or overwhelming, then decide if you should take different ones, or one here and there that you actually like.
-Look at your diet: If you are dieting and this is affecting you, then stop dieting.
-Don't eat too late or too early. Decide if your eating habits are causing a problem.
-Foods/spices: Are you eating something that is known to cause heavy sleep? Change your eating habits, in that case. You could have food sensitivities, too.
-Sleep apnea: Could you have sleep apnea? If you may possibly stop breathing momentarily while sleeping, this could make it hard to get up, or hard to stay awake.
-Have a timer set on your lights so they turn on, and this will make you more awake.
-Make a favorite food or beverage for the morning and look forward to having it.
-Place loud alarm 10' away.
-Get a check-up by the doctor in case you have a physical problem.
-Have someone pour water on you if you aren't up by a certain time.
-Make a chart and reward yourself with something special if you are up by a certain time, a certain number of days in a row.

Me also in my college days. After i found that am nt taking care of my health thts y i got tht.
Later i startd taking care of my health especially exersizing, maintaing a healthy gut, ph balance, eating more fruits, veg etc… Etc.
After all these 6 hours of sleep is going enough for me. And i got a lot of time to work