How do you discipline fibbing/lying?

[abbiebaby]

So my perfect angel who never does a thing wrong has started fibbing. He is 4 and it really just started about a month ago. Dd did this but we nipped it quicky and that was the end of it. Not working out with ds. I have tried everything under the sun. He knows what he is doing because he will eventually say if I tell the truth will I get whatever the punishment might be. I give him the chance to tell the truth without getting punished severly. For example...if he comes clean we talk about why it was wrong and he does half the time in the corner. He is not going for that and drags it on. He is worst lier so sometimes his lies are funny but we laugh when he doesn't see us. I just don't want this to stick because it is not acceptabl e. What aresome techniques that have worked for you?

Oh and the fibbing is over dumb stuff like did you brush your teeth, wash your hands, clean your room, sneak candy, etc. Small stuff that 4 year olds do. I just don't want it to turn into something worse.