Take zinc and magnesium aspartate (ZMA) before bed. Most vitamins have them in citrate form, but if you take them in aspartate form they'll help you sleep like a baby and also won't allow your body to break down testosterone while you sleep. You're testosterone levels will stay up.

Stack that at night with Tribulus Terrestris during the day (and night). The tribulus is an herb that has been used for ... ahem ... men's issues for centuries. It works by stimulating your body to produce more testosterone. It's perfectly safe and works wonderfully. Not like steroids levels, but at your age it will boost your levels to more like they were when you were 22 or so. Then with the ZMA you won't just break it back down.

Be ready for some breakouts and such though. It'll almost be like puberty hit again.