Like humans, our pets can develop bad habits that can drive the people they live with crazy. Maybe your cat begs to be let in two minutes after she was let out or likes to sprawl out on your laptop while you're using it. Or you dog jumps all over your guests or gnaws on your hands when she's feeling playful. These habits don't develop overnight. Your pet is getting something out of their behavior. The secret to stopping it is to make it unrewarding. There are a few ways of doing this.
Take Away the Reward
If your cat is driving you nuts by making herself comfortable on every magazine you try to read, chances are she's only doing it because it's gotten her something she wanted in the past- attention. If your dog begs at the table it's probably because once in awhile it's earned him a snack. Of course, it's not very productive to say "If you'd never given in, he wouldn't do this now!". We have to work with what we have today and that means removing the reward. If the reward is attention then your goal is to completely ignore your pet. That means turn your back, cross your arms and act like a tree. Don't scold or even make eye contact.
It won't work right away. In fact, it will likely take quite awhile before it works and it will definitely get worse before it gets better. Once your dog realizes that looking cute isn't earning table food, he'll probably try doing some tricks, pawing at you and finally degenerating into complete obnoxiousness, he'll probably start barking. Be strong. Ignore. The minute you give in, you're back to square one.
It is important when using this method that you make sure the whole family is on board and understands the game plan. For example, if you have a cat that habitually meows and scratches at every closed door she comes across, whether she actually needs to go through it or not, everyone needs to agree that no one will ever open a door for the cat (except perhaps the one that leads to the room her food and catbox are in). This includes accidental rewards. If you need to go through the door and the cat is scratching at it, either wait until she's done or open the door and slip through while blocking her way and close it again quickly.
This method can be used for a variety of behaviors. If your dog jumps on people, instruct your guests to ignore him until he sits nicely and then reward him with lots of praise and maybe treats. If he barks for attention, ignore him till he stops and then give him treats. If he pulls on the leash, stop moving until he stops pulling. If your cat lays on your book or laptop, slip it out from under her and turn your back without acknowledging her.
Punish the Behavior
Sometimes it's not easy to identify what rewards a behavior or the reward is outside our control. In this case you may be tempted to use punishment. If you do choose punishment it's important that it not be a violent or painful punishment that might cause your pet to fear you or feel the need to retaliate. A squirt of water or a loud noise might be appropriate. You should pair the punishment with a verbal command (like No) so that the command is associated with the punishment making just the word almost as effective as the punishment. (Like clicker training in reverse.)
There are problems with punishment. If attention is the goal then punishment may not work at all. If punishment is going to be effective it must be applied every time the behavior happens. Otherwise your pet will continue to get the reward for the behavior once in awhile and will simply be more sneaky about it next time. If your cat gets a squirt of water from you when she jumps on the counter, she'll quickly learn to only jump on the counter when you aren't looking.
Finally, punishment must take place within a second of the behavior. Otherwise your short attention span pooch may not even associate the punishment with the behavior. Punishing a dog for pooping on the floor an hour ago doesn't teach the dog not to poop on the floor. It may teach him not to sniff whatever random thing he was sniffing when you discovered the poop and decided to punish him, or it may teach him that you don't like it when there is poop there so he'd better hide it next time- or eat it.
Train an Incompatible Behavior
Your dog can't jump on people when he is sitting nicely. He also can't beg at the table if he is laying on his bed in the living room. If you are going to train your dog to perform an incompatible behavior instead of the bad habit that's driving you nuts, you first have to train the behavior. Spend some time teaching your dog sit, go to your bed, down and stay and practice until your dog is performing well. Once you're sure he's got it down, start practicing in the environment where the annoying behavior tends to take place. If your dog likes to jump on people, have a guest ignore your dog while you have him sit and stay in her presence, then have your guest pet him or give him a treat.
What Works Best
The method that will work best for your pet and his bad habits depends on the behavior and your pet's own personality. I find it's best to employ a variety of methods and usually use the first and last in combination. A qualified trainer can help you decide on a behavior modification plan for your pet. Because these behaviors most often happen in the home, it's best in that you hire a private in-home trainer or veterinary behaviorist to address bad habit issues.