Easiest way is just to learn to do it yourself lol, but anyways if you want someone to do hitsounds for you, either post in amodding queue that specifically says its doing hitsounds, or make a new post in Beatmap Projects
Make sure to read the rules/how to use posts for each of them if youre going to post in them, specifically community/forums/topics/726725 for modding queues and the first three "Pinned Topics" of Beatmap Projects