Some great information from Cliff Swain.

Facebook: https://www.facebook.com/thecliffswain
Website: https://www.cliffswain.com/

This commentary was included with the video in the original post on Facebook.

It’s easy if you:
1. Hold the racquet correctly
2. Get ready properly
3. Align yourself properly
4. Swing parallel to the floor
5. Proper contact point
It’s difficult and not repeatable if you’re flawed at any of these steps.