Go to "Team & Analytics" section on a relevant skillboard. 

Option #1: Add position to a member

Go to "Members" tab, choose a person and click on the edit icon. 

Click on "Change position". 

Choose a new position. 

Option #2: Add a member to a position

Go to "Career Paths" tab.

Choose a position and press "Add members". 

Choose members in the drop-down list.

You can also add a new member via email. Click to "+".

Choose all the members whom you want to send an invitation and click "Send invites".