You can ask your close friends to testplay and also hype your beatmap or go to
Modding Queues forum and search a Hype Queue there.
Not recommended: You can also randomly join multiplayer/in game chat channel (#mapping, #osu, #indonesian, etc.) and promote your beatmap there, ask for testplay and of course hype. surely, don't force them to hype your beatmap :p
Yes, the easiest way to get free hype is ask your close friends, that's all, for sure.
Moved from Mapping Techniques forum.