This assumes that you have already updated the modlist.

1. Open Arma 3 Launcher, go to MODS and find "Task Force Arrowhead Radio (BETA!!!)" right-click, select 'Open folder' and press 'I understand'.
2. Open the selected folder "@Task Force Arrowhead Radio (BETA!!!)", go into the "teamspeak" folder and double click "task_force_radio.ts3_plugin".
3. Proceed through the installation process by pressing "Install" and then selecting "Yes" twice.
4. Start/restart Teamspeak 3.
5. In Teamspeak, open the "Tools" menu and select "Options". Open the Addons category and make sure "Task Force Arrowhead Radio" is listed and show "Enabled".