Keep more weapons in your arsenal: Occasionally use lifting methods like forced reps, negatives, and dropsets to further stress your body. Personal trainer and fitness journalist Michael Berg explains in "6 Ways to Crank Up Your Testosterone Levels" that going beyond muscular failure with these techniques has been shown to pump up T-levels in study subjects.
While it would be nice to buy a testosterone pill from the local supplement store and have your testosterone levels go up, such a magic pill does not exist. As you can see from the above rundown, while a few supplements may be somewhat effective if your T levels are already low, none will significantly raise your testosterone above a baseline level. Thus, the basics of keeping your T levels high remain pretty simple: