cut through these strings

Making friend filters is pretty simple...go up to Manage Friends>Edit Custom Friend Groups. From there you just make a new group, give the group a name, and put anyone from your list you want to be in that group. Then when you're making a post, go to where it says Security and select "custom". Some little boxes will appear with the names of the groups you've made. Select the box, then only the people in that group will be able to read your post.