I fold up the cue sheet so that all the calls between the relevant controles are visible, then place in a sandwich-sized zip-lock. Zip-lock resides in my jersey pocket and I pull it out from time-to-time to check it. Cue sheet gets re-folded at each controle to set it up for the next one.
Somewhat related questions: what information do you like to see on the cue sheet that's been provided to you? Is there such a thing as too much information used to describe route information? I'm working on two, 200K permanents and would love to hear others' thoughts on the good, the bad, and the ugly when it comes to cue sheet information, format, etc.