There is nothing inherently wrong with telling your dog “no,” except that it doesn’t give him enough information. Instead of telling your dog “no,” tell him what you want him to do. Dogs don’t generalize well, so if your dog jumps up on someone to say hello and you say no, he may jump higher or he may jump to the left side instead of the right. A better alternative would be to ask him to “sit.” Tell him what you want him to do in order to avoid confusion.

Changing behavior takes time. You need to have realistic expectations about changing your dog’s behavior as well as how long it will take to change behaviors that you don’t like. Often behaviors which are “normal” doggie behaviors will take the most time such as barking, digging and jumping. You also need to consider how long your dog has rehearsed the behavior. For example, if you didn’t mind that your dog jumped up on people to say hi for the last seven years and now you decide that you don’t want him to do that anymore, that behavior will take a much longer time to undo than if you had addressed it when he was a pup. Remember it’s never too late to change the behavior some will just take longer than others.
Unless you plan to keep your dog outdoors--and few of us do because it's not recommended--you'll need to teach your dog where to eliminate. Therefore, house training (also called housebreaking or potty training) is one of the first things you need to work on with your dog. Crate training can be a very helpful part of the training process. This includes house training as well as many other areas of training: