Well, you have to focus on your goal before sleeping.
For example:

If you are going to wake up early and try to do WILD, focus your intent on waking up at that time.

If you plan to do MILD then focus your intent on waking up after each dream period.

I understand that it is hard, but you can;t let your thoughts wander, it means your losing conciousness.So be careful about that.(I do it often)
Oh yeah, welcome to the forums!!