Search game with handkerchiefs

Take four handkerchiefs of which you have carried 2 in your pocket for a day.
Stretch a line at eye level of the dog and hang the two ‘odorless’ and one of the ‘worn’ handkerchiefs with a clothespin. Allow the dog to smell the remaining handkerchief from your pocket and point it to the clothesline. Give the command “find” and track the dog to smell the hung handkerchiefs. It is the intention that the dog ‘points’ the handkerchief that smells the most to you.
If your dog understands this (so if he has pointed out the right handkerchief several times in a row), you can also hide the handkerchiefs on the floor under three identical upturned pots and play ‘ball-ball’.