TIP #1: EXTINCTION BURSTS
We've all had this happen to us before: we are checking out at the store and we slide our credit card, but it doesn't work. We slide it again. Nothing. We slide it harder, faster, and upside down. Still nothing. This is called an extinction burst: one's reaction to a stimulus that once produced positive reinforcements, but that ceases to exist. Extinction bursts are quite common when trying to eliminate a dog's behavior, especially attention seeking ones (barking, jumping, etc.). We ignore the behavior, so the dog tries even harder to produce those positive reinforcements that came so easily before. But be patient. Behaviors that are no longer reinforced become less probable, leading to extinction.
TIP #2: HAVE REALISTIC EXPECTATIONS
Most behaviors that we find to be a nuisance - barking, digging, chewing, etc. - are really normal, everyday doggie behaviors. Many of those behaviors are genetic, or have been habituated by years of reinforcement. They can't be changed overnight. It takes time, patience, and consistency.
Jeff Dentler, CPDT-KA, CTDI