Welcome to the joy of snuff. I have been snuffing off more years than I care to remember, and I still get the odd spot of snuff down my front.
The best technique to avoid mess is the wet finger. Lick your finger dip it in your snuff and rather than sniff, apply it to your nose. But you don’t want to do this in public. The second best is lick the back of your hand, put a pea sized pinch on the wet bit and then cover it with one nostril, sniff and brush anything left on your hand with a handkerchief.