How to apply the group into your unturned character :

1. Go to unturned main menu there is Play, Character and Option. Click " Character ".

2. Click the "group" then choose our group among the list of steam groups that you have.

3. In the nickname type our group name so that when ingame other members will know that you are a clanmate.

4. After you've already joined the server press L in order to chat to group members only.