I went to a clinic that specializes in it. They take several blood samples and send them off to the lab, the test for overall testosterone levels, free testosterone, estrogen and one other I am not 100% certain of.

There is a range that is considered normal testosterone except that range is HUGE, my results were at the very low end of that spectrum.

Part of the plan I am on I get tested every month for the first 3 months then every 3 months there after.

You can get home kits. You just give them a couple drops of blood and send it back.