Step 1: Navigate to event setup >> edit event >> and then open the capacity tab. Then, scroll to the waitlist settings at the bottom of the page.
Step 2: Click the edit link shown here:
Step 3: Check the box in the column that reads Display Waitlist Icon? Save your changes.
Navigate back to your registration page. You should now see a Waitlist option in your event menu:
Not seeing the waitlist tab? No problem, if there is no one currently on the waitlist, the tab will not appear. If you do have someone on the waitlist, then perhaps try refreshing your participants.