Licking your wounds can help. It's instinctual in animals for a reason.
Licking can remove dirt and debris from the wound, decontaminating the area. This is useful, but also not very safe if there's something sharp in the wound, since then it's just going on your tongue. Saliva contains bacteria-preventing components as well.
And, the most obvious fact, licking your wounds closes them.
But, do not do this if you can. This is not safe in everyday situations. If normal medical help is possible, it should be seeked. And, as always, it's better to not do this to a larger wound.
If you were wondering.