1 Many people use indoor tanning beds to get a base tan before going on vacation, particularly if they are traveling to tropical destinations. 2  To develop a good base tan before going on a vacation, start tanning indoors 3 or 4 weeks before your intended departure date.ips. 1  Many people use indoor tanning beds to get a base tan before going on vacation, particularly if they are traveling to tropical destinations. 2  To develop a good base tan before going on a vacation, start tanning indoors 3 or 4 weeks before your intended departure date.