I'm with Cinder&Smokey (& others) on this. The dog has to be gently shown that everything is not a fight. That cooperation brings joy.

The dogs I work with are often over a hundred to 150 pounds, about as big as sheep or small horses.

What works best is not treating an individual problem like a spot treatment. You are not trying to fix a single misbehavior issue... what you really want to do is set the tempo for the rest of the dog's life by teaching and rewarding self control.

One of the best ways to do this and gives much success with problem dogs and rescues that I know about, is safe to use and can be used with shy dogs or aggressive or simply hyper, manipulative dogs, is to use NILIF principles. It is the acronym for "Nothing In Life Is Free".

I encourage people to do a web search on NILIF, read several pages on it and then formulate a way to get the entire family involved in teaching the dog self control via NILIF.

The dog then learns that "Hey, this person and their entire family are not slavelike petting machines!", "they are not treat vending machines!"... "so if I sit quietly and pay attention, I will earn what I want". Baby steps. Consistency, respecting the dog too... and even the biggest clumsiest lug of a dog learns to respect his people and defer to them better.

Edit to add, yep (agree with the others) bring the dog in to the vet too, get shots up to date, and discuss scheduling a neutering or getting info on where to get discount neuters. Some locales will neuter pitbull types for FREE.