doing a lot of power training increase your test production (squats, cleans,bench press, deadlifts, t-bar rows)
if you eat clean you will produce more test especially eating peanuts and almonds
there are lots of legal suppliments claiming to increase your test but i don't know how well they work. I am currently experimenting with tribulus but i think if it were magic then there would be lots of hype about it. All i have found so far is random bonners throughout the day but I am 20 so my test is through the roof right now. I do know of some legal stuff called 6-OXO with is often use for people comming off sterioids to get there natuall test production back in order and prevent bitch tits. If I were gonna try anything i would try that. unless you wanna get involved in PH's. I just did a cycle of M1T and gained 18 pounds in 17 days!!! but I too want to keep up a strong natural test production.
if you have any luck with your research drop me a line I would like to do the same thing you want to