That's great. I do the same thing, I'm getting up at 5:20 now. It does get easier. A couple weeks later it's a lot easier, a few months in and it feels normal. My appetite for sleeping in has kind of gone the same way junk food did - I hardly want it anymore (but still do once in a while).
The single thing that works best for me - absolutely without fail get up as soon as the alarm goes off. Laying back down kills me. Pretty soon it becomes a habit - alarm, turn it off, stand up and into the bathroom. Sometimes I sit on the toilet with my eyes closed
but by the time I'm done with that, washing, weighing and putting my workout clothes on straight away, I'm awake (not necessarily perky
)
The other important thing for me - consistency. I still get up early on the weekend. I don't set an alarm, but I don't lay around in bed. I was sleeping in until 6:30 or 7 but that didn't feel good, so now I'm moving it to 6 or 6:30, and hopefully 6 will become the norm on the weekend.
And if I have a late night, I *do not* use it as a reason to sleep in. If I do, then I can't get to sleep on time the next night, and it's a vicious circle. Just get up early anyway, you'll be tired enough to go to bed early the next night, and you'll be right back on track