Here's how to add additional parts to an existing motion capture recording that you've made.
Step 1. Load the recording in the Recordings menu.
Step 2. Click the Add New Part button along the bottom of the menu.
A countdown will begin and then Flipside will start recording.
Step 3. Perform your scene. Note that if you have multiple users connected over multiplayer, any user who is in character will be added as a new part at the same time.
Step 4. When you're done your scene, open the main menu again and choose Stop Recording.
The Recordings menu will appear, asking you whether you want to keep or discard the recording you just made.
Step 5. Choose Keep Take to save the recording.
You'll see the new recording take a few seconds to save, which also backs it up to the cloud.