To send a response to an invitation you receive, view the invitation email and press the ‘RSVP’ button or the ‘View Invitation’ button. If you receive your invitation via a text message, click the link in the text.
On the invitation page, click "RSVP" in the upper left corner.
Select the appropriate attendance option from the list and follow any additional steps (such as adding additional guests).
Once you confirm your option, you can choose to ‘Message the Host’.