You can definitely leave your Sugar Sand Tan Mousse on as long as you’d like. Some people prefer to sleep with it on overnight! You can also apply before going out too! Will not mess up your clothing!  Just be careful not to get wet or sweat! Stay cool and dry for the first 8 hrs. This formula sticks to you and not your sheets! Yay…keep your sheets clean while tanning! My favorite way to tan is in the morning…Apply…dress and go!  I just keep getting darker all day!