Sleep with earplugs, use clothes pins to hold the curtains closed, stuff all light leakage with extra pillows, sofa pillows - get the room as dark as possible. Keep the room cool. I tried the white noise routine - it doesn't work when the in room air conditioner "Ker-chunks" on every 20 minutes. Good ear plugs work great.

Sleep as much as possible. It's all you can do. Unfortunately, you'll get used to flying tired.