I'm currently taking 2mg once a week on my rest day; I started with 1mg and after 1 month added another MG. I'll continue each month until I reach 8MG once a week, which is the dosage the doc I worked with in Texas to get my prescription recommended and most people seem to take.
Also - I would say that NMN + Rapa is a completely life altering combination for anyone 50+. I feel like I can lift harder and longer now than when I was in my 40's and things seem to be getting easier the farther into my rapa routine I get.
Also also - you can find rapamycin online / overseas under its other name - Sirolimus - and the cost is a little lower than getting a proper US prescription.