I am forgetful, distracted, and terrible at estimating how long things take to do. This means that breaking down projects into tasks and managing those tasks is important to me.
Or, How I organize my brain
Big picture planning:
Happy planner
brainstorming composition notebooks with graph paper
dedicated subject/project notebooks -- preferably arc-style with dot grid paper
In order:
Workflowy
Evernote
Remember the milk