I used to have this problem a lot. I even had a problem where I would think of doing one thing, but I would do another.

The easiest solution I have found is to say out loud what I am doing as or before I do it. It sounds and feels kind of strange at first, but it really works. You get more sensory input about what you are doing. Maybe you remember your mouth forming the words, or you can recall what you just heard yourself say. Try it and see.