Method 1:
Wake up consistently every day for a while, it doesn't matter what time, but do it consistently (and set an alarm).. and possibly develop a routine around it (like brush teeth, read book, bed).
Then you can start adjusting it a half hour earlier every couple of days or something to tune it to where you want.
Method 2:
Get an alarm that plays a custom sound clip. Record your own voice reminding you that you're trying to adjust your schedule in the morning.
Method 3:
maybe you have a biological or psychological problem that you should fix first; not necessarily something worth a hospital visit. Hygiene, diet, good mental health practices, are all important... but then again, keeping a steady routine can keep you more stable.