After a couple of years on third shift I found it difficult to reacclimate to a "normal" schedule. What ultimately worked for me was taking a gradual approach.My standard wake-up time was 2:30 PM.

Week 1: I made sure I was in bed, lights out, by 11 PM. I would set my alarm first alarm for 11:30 AM, and a second for for 1 PM. I would also leave a water bottle and a dose of caffeine pills next to my alarm. When the 11:30 AM alarm went off, I'd take the pills. Then, when my 1 PM alarm went off I was alert enough to drag myself out of bed (and leave the bedroom until I was really awake).

Week 2: Same thing, except I rolled the alarms back to 10 AM and 11:30 AM.

Week 3: Same thing, roll the alarms back to 8:30 AM and 10 AM.

Week 4: Same thing, just 7 AM and 8:30 AM now.

Week 5: Same thing, moving to the final time slot of 5:30 AM and 7 AM.

Weeks 6-12 (at least): Drop the caffeine and first alarm. 7 AM alarm, across the room, no snoozes. Life long habits.