The easiest way to create a 1:1 for the purpose of discussing a review cycle is via Team Reviews. The main benefits of doing so is that much of the 1:1 creation form will be pre-filled for you and the 1:1 will automatically become associated with the desired Review Cycle.
Start by heading to Team Reviews via the sidebar and selecting the appropriate Review Cycle from the list presented to you.
Look for the person on your team that you wish to schedule a 1:1 with, then click on the Calendar icon under the Actions column for their row.
You will then be taken to the 1:1 creation screen with much of the form already filled in for you.