Well, I'd suggest anticipation.
I.e. sort out a cross-country route, including things like MATZ crossings, zone transits, circuit joining, etc., and write down the calls you expect to have to make, and the likely replies and requests and instructions from ATC. That'll refresh your memory.
If you've time, plot another route, with similar complications, and ask another pilot to play the part of the various ATC agencies, with you interacting as appropriate.
Also, think through to yourself about the differences between ATC, AFIS, and A/G, and be clear about what they mean.
Good luck!