Most cats are very well mannered and polite.
However if they do display unwanted behaviour you literally need to be there on the spot if you are going to punish them. Otherwise your cat won't associate the problem with the punishment and will only become stressed and confused. If your cat has started a bad behaviour such as jumping on the kitchen bench or climbing the curtains, have a water pistol at the ready and squirt them when you see them doing it. Make sure you do this quietly so your cat doesn't see you. If you see your cat about to do something naughty, gently and quietly redirect their behaviour to the appropriate place, for example direct your cat to the scratching post if they are about to scratch the furniture.
Most cats learn very easily with positive reinforcement. Praise them when they do the right thing! WHISKAS® CRAVERS® are a yummy treat you can use for a reward when training your cat.