I have pretty much exclusively trained first thing in the morning for like 4 yrs now, and I absolutely love it.
I would definitely invest in some whey &/or bcaa supplement. I don't know how you feel about preworkout supplements (I know some are really strong and make some people jittery). If you handle coffee, I don't think you should have too much of a problem.
I wake up pretty much everyday btw 4:30 - 5:00 am. I take my preworkout and add in some bcaa (you could add some simple carbs if you like). I use this time to prepare/pack my food for the day and allow for the preworkout to kick in. By 5:30 - 6:00, I'm ready to go.
I would also recommend mobility exercises/foam rolling to get the blood flowing, warm up the major joints, and get some ROM.