Welcome!  English (US) Language Switcher

Click on 'Contacts' at the top of the page.

Click on the 'Contacts' tab (if you're not already there).

Select the contact(s) in the contacts list who you wish to add to a group.

Click on 'More Actions...'.

Select a group under 'Add to...' in the dropdown.

The selected contact(s) will be added to the chosen group.