I just did Aerosim freeplay mode a couple times a week to keep up to speed with flows/profiles. I also did the daily grind every so often to keep my head in memory items and limitations. I know it's really dry reading, but it's also a good idea to get your head into the LROM from time to time to keep refreshed on all that stuff (that oceanic checklist is really helpful for studying).

Doing just those things, I felt pretty good going into OE. Hope it helps!