Don't stand on the crutches with your weight supported by them against your armpits. Nerve damage can happen.
Use the crutches like your own gym. Come up with exercises to keep the boredom away. Use them to work the abs too!
this all assumes you're non-weight bearing on crutches.
R1200RT (R1100RT gone)
Don't be the guy who needs to pee on the fence to figure out that it's electrified.