Every child should have a naughty corner or room whichever is easier for you. I feel that when I put my son in a seperate room if he has been bad he realises that he has done wrong. He doesnt like to be left alone so finds it more rewarding to behave and he gets to stay with us in the living room. If he is bad he is put to his bed with no toys which he doesnt like and I find this works well with keeping him well behaved.