I tend to scold the dog with a light hit on the nose, and then I send him away.
Tip I read is to send your dog away from you, for punishment, rather than to call it over to you and then punish it.
It'll learn to accept being called to you as being part of being punished, which you don't want.
And also, don't punish the dog after it's done something. If it's gotten into bins or whatnot while you're not at home, don't punish him when you get back, as the dog won't know what it's being punished for.
But yeah, a smack is fine, so long as you're not properly hurting the dog.
I also use a spraybottle filled with water. Squirting it in the face will let it know it in trouble. And if they're barking and whatnot, then it tends to stop them. My dog pretty much stops doing anything when he sees the spraybottle, which is a good thing.
this is an honest to god question.
how does water tell him its wrong?
Dogs, like most people, don't like water being sprayed in their face. It's a punishment to the dog.