All the time

Ebony mail, muffled Ebony boots, Daedric bow at 122, and Daedric greatsword at 144, 4 perks in sneak, 3 on the first, and the one on first left, 50% less noise or something (can't remember right now).. What my bow doesn't kill, my greatsword will.. They never knew what hit them..

Just put muffle as one of your two enchantments on your boots.