If you would like to send out a calendar invite with your interview requests on Martian Logic, and haven't set up calendar integration, please follow these steps.
1. Move a candidate to an Interview stage (needs the interview milestone)
2. Click the settings icon in the top right

3. Choose the service you want to integrate with:

4. When completed, the screen will look like this:

5. From now on the interview dialogue will show who you are linked with.

Now when you send out an invite it will be included in the email and automatically added to your calendar as well.
Hope this helps!