You need to get Testosterone Injections from your Doctor, Low T Clinic/Mens Clinic, or Endocrinologist. Me and other people I know have tried it and it will make you feel like your an 18yr old again. Trust me! Easy fix.
70 isn't that old! My father in law is older than that and his apparently works fine, considering the number of ladies he goes out with. I would suggest practicing at home on your own, and see how it works! You may be surprised! If you need a little help, vara is a wonderful product. My friend uses an over the counter pill called Kangaroo, and it works great and reasonably priced