This post is inspired by a friend who just asked me how to use sage.
As per an article on Chopra.com by Bess O'Connor Smudging is an ancient ceremony in which you burn sacred plants, such as sage, to allow the smoke to clear and bless a space.
So here is what I personally do:
I walk around our apartment in New York City with burning sage (my friend sometimes gifts me hand-picked sage from Utah) blowing carefully into it (see photo) to create smoke.