Make sure that you and other interviewers integrated their calendars and email accounts in Settings / Integrations. Then open candidate's profile and go to the "Interviews" tab:

If you don't need to check your interviewer's availability and plan to schedule one simple interview, then click on the "Simple interview" button, you'll see something like this:

Use "edit Interviewers" link to choose interviewers:

Choose interviewers and then click the "Save" button:

Click the "Save and send invites" button:

Review the calendar invite that will be sent to interviewers and click "Save"

The interview will appear on the "Interviews" tab:

Gray circle near the interviewer's name means that the interviewer hasn't responded to the invite yet. If the circle is red, the interviewer has rejected your invite, you can edit the interview and resend invites. If the circle is green, the interviewer has accepted the invite:

Make sure that your interviewers have accepted calendar invites and then invite the candidate on the "Interviews" tab:

You'll see the same calendar invite preview as you've seen when you were inviting interviewers: