Try to limit the number of times you’ve to tackle the stairs in a day - make sure you’ve got everything you need before you head down in the morning & if you’ve no downstairs loo see if you can make trips up coincide with other things you might need to do.
As a PP said, make sure you’ve your painkillers & a waterbottle in your wee bag; in addition to that, make sure you take them on time, don’t wait until you’re in pain. (Realise that’s not so much about coping on crutches, but trust me, it’s important!)
If you’ve got someone who can help you with things like washing your hair, don’t be embarrassed to ask.
If you can afford ready meals/things you throw in the oven/pre-prepared salad etc, stick with that for a bit.
Nap if you get the opportunity. Being on crutches is exhausting.
No shame in wearing your PJs if you’re not going out - they’re comfy & easy to get on/off when you’ve a leg injury.
Hope you feel better soon OP 
