Draw others into your MAP or, if that’s not possible, write to your future self … but don’t cheat by “doing a MAP in (only) your head”!
Even if MAP is a simple tool, using it well is not so trivial. For example, you have to check that objectives are immediate and multi-directional as well as envisaging your audience and game-plan. It’s easy to get muddled and overlook something if you rely on grey matter only. By emailing the MAP to a colleague, or by talking to them, the whole thing becomes much easier, and more useful. If this is not possible, just write it down for yourself, to be read at some far off date, when all has been forgotten.