Go to the group that you want to add the contact to and select Add.  This will bring up a box that will offer you the options to manually add a contact. You will need to check the box to opt-in the contact which will take you to the screen of terms and conditions which you must click ‘understood’  You will then be taken back to the Add Contact option and you can choose to manually add your contact.  You will then see a box to add your contact information