I used to get scented deodorant so I was able to smell the fragrance under my arm and know that it was applied. But unfortunately the brand I use has discontinued the scented version and I must now use an unscented version. Often I can't remember whether it's been applied, and end up applying it again to be sure although it's likely that it had already been applied. There may be times when I have applied deodorant three or four times.
How can I know for a certainty if I have already applied unscented deodorant / antiperspirant?
Note: The type that I am using is in the form of a roll-on stick.