How do I keep my mosquito bites from itching?

Apply heat on it, buy one of those pouch design for storing hot water, boil some water and apply it to itch it always work for me and the heat helps blood flow better so it reduces swelling by a lot

Use calamine lotion, caladryl cream, benadryl cream, campho-phenique ointment, hydrocortisone cream, or many other over the counter remedies.

Try rubbing alcohol. You can also try wetting some oatmeal and putting it on there.