I forgot how to use the oven once.
I also forgot how to use the dryer.
In the car I always forget which is the brake and which is the gas. Even if I think I might know it, I still ask just to be safe.
A lot of times I have a problem with forgetting where I'm walking to. I could be walking to class and then have no idea where I'm going. My mind just goes blank. I always just continue walking until I can finally remember where I was walking to. I figure that's better than just stopping and standing there looking stupid until I remember where to go.