By default, If you track someone on Slated, or if they have a credits score that equals at least half of your own credits score, they can message you. In addition, anyone who you don’t track but with whom you share a mutual connection can “request an introduction” to you through that mutual acquaintance. (It is up to the acquaintance whether or not to make the introduction.)
However, you can adjust who can message you on Slated by going to your Settings page, where you can expand the people who can message you on Slated based on a different score threshold, or allow anyone on Slated to message you. You can also restrict who can message you to only those members whom you track, or to no one at all.
Please note that when you return to your home page, you will not see a change in the way that your messaging settings appear - since you cannot message yourself, the message button will appear the same regardless.