We all have off days, I'd rather not thing about the times I've tried to start the engine with the windscreen wipers.
Try and develop a muscle memory of the actions so you don't have to think about them, you should find that you don't make so many errors if your subconscious actions are sorted.
Also always try and remain calm, plan ahead to give yourself time to act and don't worry about the little things.
I think I do plan ahead, and it's when it changes that I panic. I find it hilarious when I do something stupid...my driving instructor has quite different views!