Toothpicks were invented to aid in the removal of food stuck in between your teeth.
Toothpicks should be used in private and should never be used at the dinner table. If you have food stuck in your teeth, excuse yourself and go to the restroom to remove it.
Once you have used the toothpick, discard it. Do not walk or drive around town with a toothpick dangling from your mouth. This is especially important to remember when you are on a date so you don’t stab the person you’re saying goodnight to with a kiss.