Why does Stanley give the lipstick to xray?

Stanley gives the lipstick to X-Ray as a gesture of goodwill and to gain favor within the group at Camp Green Lake. He hopes that by offering the lipstick, which he found in the desert, X-Ray will help him by putting in a good Word with the camp's authority figures. This act signifies Stanley's desire to fit in and establish friendships, as well as his understanding of the social dynamics at play among the boys.