How do you remember flying knowledge?
+1 accident reports (I read them in flyer). Also at my airfield there is a newsletter that always contains a problem, there are also occasional problems posted in the briefing room.
Have you considered compiling a list of potential problems some annoying (eg. Landing light out/frozen pitot) some serious (rough running/oil pressure drop/EFATO) and trying to solve one each week - not just saying to yourself I know what I'd do, but maybe write down each step you think you'd follow from identifying to solving and then look it up or speak to an instructor to be sure you haven't missed anything.
Happy landings.