You've got a very small amount of PC which is very natural with aging. The majority of men your age are walking around with a small amount of PC and don't know it, and most will never know it and it won't bother them. Keep that in mind. What sets you and them apart is the very thin line that they, unlike you, did not go through the set of circumstances which led to a biopsy...that's about
all.
So your decision to not rush into a potentially unnecessary and aggressive treatment appears smart. Sure, you could treat it now...but why put yourself through that if it's not needed? The scope of PC overtreatment right now is overwhelming...men with low-risk PC thinking fast, aggressive treatments "saved their lives" is widely recognized in the medical profession as a fallacy. And believe me, the forever side effects are significant for a significant number of people; these pages are full of stories of men with ongoing issues. Definitely you will find some men who were diagnosed with low-risk disease (like you) come here to express treatment regret with the hopes that others do not follow in their footsteps.
So what is life on active surveillance like? As you noted, it will include periodic (perhaps twice a year, at first) PSA tests to monitor things. There will also likely be a follow-up, confirmatory biopsy around 12-18 months from your first diagnosis, and then probably again in a couple years. Looking forward from that, probably other imaging technology will replace the trans-rectal ultrasound (TRUS) biopsy, or you may continue to have it "the old fashioned way" every couple years going forward. I agree with John T that MRIs today are alot different than in the (recent) past. about a third of men eventually find that their follow-up biopsy results have tipped the scales to the point that they move on to treatment, while the others can continue monitoring over the long haul. The philosophical question is: "for which low-risk patient is AS the TRUE success? The patient who moved on to successful treatment? Or the patient who completely avoided treatment?"
Some men are initially uncomfortable with the idea that they have a small, indolent tumor in their prostate, but patient education over time helps them to understand that this is normal aging and that their risk is low. Initial fears are often overcome when they also see what their friends & colleagues suffer through as a result of the serious side effects of (over)treatment of PC.
Lifestyle choices (diet & exercise) and stress reduction as a means to stop "feeding the cancer" are a part of all the best AS programs. If you want to take it seriously, you will adopt these, too, and make sure your monitoring urologist is well-versed with the latest info on AS (or else find one who is!!).
My recommendation is to spend time learning more about AS. For starters, Google the work of "Dr Laurence Klotz." Spend some time learning...there appears to be no need to rush...consider yourself lucky to be one of the ones who learned more about the natural biology of prostate cancer before rushing into treatment.<!-- Edit -->