If you want to assign a friend to a group*, let's say Diana to YateTeam, do the following:
- locate the ID in your Friends list and select it;
- right click it and select "Edit" or go to Main Menu->Friends->Edit;
- in the details screen that appears, you can either:
- check the already existing group and then press "Ok"
- or Add New Group, then press "Ok" (it's automatically selected when "Add" is pressed)
If a group is left without any friends that belong to it, it will be deleted.
A friend can be a part of more than one group, and, when "Flat list" is unchecked, will appear in all of them.
Please note that for the time being, Facebook* allows you to make changes in your friends list only logged onto Facebook site.
Screenshots are from 3.2 versions of YateClient or older.
* See here what features and limitations has Facebook chat, although it provides compatibility with XMPP clients, such as YateClient.
If you want to add/delete friends, organize your groups, you must do these changes logged onto Facebook site.