To make things easier, employees are able to sign themselves up as advocates. This option can be turned on and off within the board's Settings tab.
Once turned on, you will be able to share the sign-up link with users from your company and have them join on their own. Note that users who join this way will still count against your license limits.
If you choose to enable this option, anyone with a link to the sign-up page will be able to join your social board. For this reason, we recommend that you whitelist your company domain to prevent unwanted sign-ups.