I know exactly what you mean. After a bit more reading about Mars in Gemini, I can relate. The scatter-brain mentality definitely applies to me. I have my to-do list book and the aim of the game is to cross off as many tasks as possible. I always start with a 'fake'/placebo task though, just to get me started.
ie. drink a cup of tea
The action itself, of crossing things off, motivates me enough.
In regards to the actual goal-making, I also suffer. I've tried loads of different things like uni and jobs etc, but feel as if I could excel in anything if I put my mind to it, but don't think that mentality serves we well because I then get lost for choice.