If you can remember everything you're supposed to be doing, you're not doing enough.
This is the reason by CRMs and contact management software is such a crowded industry, but what about your notes and ideas?
I've been a fan of EverNote, StandardNotes, and a couple others which are good for long form content, but there's a new tool on my radar that is incredibly powerful.
This is a database program that has some particularly nice features that I like (most of all is the fact that you store your files locally on your laptop instead of on the cloud).
Instead of repeating a lot, here's a good intro video: