Navigate to your LEO unit. From the Administration menu select Unit administration > Users > Groups
Select your group from the column under 'Groups:', then click 'Add/remove users'.
On the next screen there will be two columns: 'Group members' and 'Potential members'. Clicking on any of the users from the right hand column and then clicking on 'Add' will add them to your Group. You will see their name is now displayed in the column on the left hand side.
You are able to add multiple students/users to your groups in LEO by holding down the 'control' button (PC) or the 'Command' key (Mac) and clicking on all of the users, then clicking on 'Add. You can remove students/users from your group by clicking on their name in the left hand column and then clicking on 'Remove'.
You can also search for specific users in either the 'Group members' column or the 'Potential members' column by entering a name in the search field underneath the appropriate column. If you click on 'Search options' further options will be made available to you.