Today I kept track of how many cigarettes I smoked by writing a tic mark on my wrist for each.
My first impulse was palm or back of hand, but I wash my hands so much during the day that any ink there would quickly wash off. Plus, a wrist is well enough hidden under a sleeve that it won't look unprofessional, yet I'll still see the marks regularly.
That's seven. Maybe one more tonight. Not too bad!