I don't have the best memory – if I relied solely on memory from gaming session to gaming session, I would definitely forget at least one medium-to-big thing that happened, much less the little characterization points and minor incidents. And that's if the sessions are regular and every week. Don't even get me started about every other week or irregularity.
A recent method of compensating for this I've been using is chatting with my partner about the last session at random points throughout the week, between sessions. Which is less about actively trying to remember things and more just being excited about the campaigns I'm playing in.
But, the method I've been using the longest has been to take notes during the session itself. Which is how I have a binder full of handwritten notes from the three-year Exalted campaign from college still sitting on my shelf. That was back when I still drew, so there's a couple character and artifacts drawings in there too. I think there's even a group portrait in there. I ended up being the one taking notes because we played without computers, iPads, or any other electronics and I was the only one with legible handwriting. I'm not boasting there, I'm being literal – one of the guys paid for folks to take notes for him in class because his handwriting was so bad, another had a benign hand tremor (which meant terrible handwriting), and the third... I don't remember what was up with the third dude. It may have just been generically bad handwriting. Eh, whatever, I regularly got extra experience points for taking notes and being able to tell the GM the name they'd used two sessions ago for an NPC.
Note taking these days is really different since the group that meets most regularly is getting together over Google Hangouts. So I could be taking notes electronically, pretty easily. And yet, here I am with my handwritten notes.
Yes, I do type faster than I write, so on occasion, handwritten notes slow the game down. But, I do remember things better for putting the information through my muscles by writing, instead of typing. Plus it keeps me from opening up that new tab and partaking of the distraction that is the Internet. On the one hand, unless I start photographing or scanning my notes after every session, it's not like I can share them with the group, like Greg has been, in order to keep the game information fresh in everyone's head. On the other hand, I really dislike trying to note things in PDF files (which I would need to for my character sheets) and having the paper copies is easier to glance through than scrolling through open windows on my computer.
I think I'll need a more systematized method once I'm GMing a campaign, one I can notate stuff really fast in since I'll need to keep track of characters' actions, not just my own. But for now, this is working.
Anyone have some methods, tool, or tips and tricks to share in the comments?