Before I go to bed, I sometimes take 250-500 mg of L-Theanine, 1 gram of GABA and a few other herbal stuff. This composition, makes me feel me feel as sleepy, as if I had drunk 2 or 3 beers.
I'm not sure if Melatonin ever worked for me, but L-Theanine and GABA, surely calm me down.