How: Heat up a metal spoon under hot tap water for a minute or so, then press it directly against the bite. Hold it tight against your skin for a couple of minutes, and when you take it off, the itch should be gone for good.
Why: When mosquitoes bite you, they inject proteins under your skin to keep your blood from clotting. It’s this protein that causes you to itch, but it can’t survive at the moderately high temperatures a hot spoon can create. The bump might linger for a few days, but the uncomfortable itching should be gone for good!
Do It And How 
Mosquitoes love me. I used this method just last week and it does work.