no-nix-hannah said:
You don't need to make it bigger as the older you get the proportion of size in regards your overall body mass increases anyway. The older you get you shrink in height but your penis stays constant, therefore, live to 120 and you'll be pleased with how 'big' you are.
Except your ribcage sinks into your abdomen as you age, pushing it outwards and downwards.
This is the reason old people wear trousers so high up; with men this has the effect of reducing the ammount of visible penis, as the root is still anchored to the pelvis, so in actual fact it will appear to shrink as they age.