No caffeine after 3 PM (5 hr half-life, 25% remain at 1 AM), no water/drinks after 8 PM, going to bed at a regular time, and of course a mix of cardio/resistance exercise (see CDC for guidance).

Aside from that the only other thing I've found helpful is, counter-intuitively, skipping meals. First few days your body remembers that you're "meant" to eat then (i.e. hunger), but after that you get a strange energy boost instead. So if I skip breakfast/lunch I often find myself with MORE energy mid-afternoon, even if you'd expect less. I do get a little hangry/irritable at dinner time however.