Do you lean your head back and pinch the nose with nosebleed?

Partly correct. Things you can do yourself for a mild nosebleed include 1. Sitting upright to reduce the pressure in the veins 2. Lean forward to avoid swallowing blood 3. Pinch both nostrils shut for 5 minutes or so you can repeat these steps 3-4 times. Seek medical attention immediately if it hasn't stopped by then.