How to get rid of a hickey?

hey everyone , i have lately gotten a "big" hickey , its on my arm ... well , a few on my arm but only one big one . I am still in Elementry school . i'm in grade six. I don't want my teachers , friends , parents or enemies to see it !! .. I have been wearing long sleeved tee -shirts but .. My friends ALMOST saw it !!! ... I dont know what to do :(