Locating drafts

This morning, I twitted on a way to locate drafts in the home. Drafts come from pints of egress/ingress and windows. If a house is poorly made, drafts can originate from any number of places, including locations where pipes enter the house.
The twit concerned itself with lighting incense and passing the burning stink stick ( I particularly don't like incense and it's not good for respiratory issues) over the edges of the frame. If the the smoke dissipates, you've found the draft.
Hunters, like my self, are concerned with the direction of the wind least we spook elusive game that can smell us. I simply toss loose soil in the air. Some hunters use fine powder (like talc) in a bottle and squeeze, ejecting the powder which is carried on the wind. This possibly could be done locating drafts, but I imagine it would create a film of dust where ever it setteled and wouldn't be too pleasant f one were to inhale it i imagine.
Another way to locate drafts is to hold loosely three or four squares toilet paper and pass it over the frames slowly.
Though once a draft is located and fixed, doesn't mean that is the end of your problems. Older windows with just one pane are not well suited for keeping warm air in and cold air out as a pane is not a good insulating material and heat is lost and cold is gained though convection. Same thing with a thin door with out insulation. That is why is is best to get top quality energy efficient windows.