The most confusing part of this tutorial is the section on "reverse stabilization" in the first part. Here's a cheat sheet to help out with that and other details:
MORE DETAILS FROM THE TUTORIALS
When filming, make sure the actor's face stays square in frame (this will make the tracking easier).
When tracking the footage, in the Tracker window, click "stabilize motion" in Tracker window. Make sure your track type is selected as: stabilize (this is a different setting than from the previous tracking exercise – that track type was set to "transform"). Select both Position and Rotation.
The corners of the eyes are usually good tracking points. Under "analyze," click the "play" button to analyze forward. If the track isn't doing a great job, you can go to middle of footage, reset track points, then analyze forward and analyze backward. Also, you can manually adjust points frame-by-frame (click on the frame and re-position the big square targets). Hit "Apply," then you will get your footage floating with black corners (as the edges of the tracked footage rotate through space).
To fix the black edges, you'll pre-compose the footage. To keep track of which is which, use this naming convention – call your first comp "Original Footage," and the new comp "Pre-Comp Footage."
Layer > Pre-compose > Move all attributes into new composition. This is the one you'll call "Pre-Comp Footage." A "pre-comp" is essentially a nested layer of series of layers in another composition.
This is where it starts to get confusing in the tutorial. But here's a summary.
View both comps ( "Original Footage," and "Pre-Comp Footage") stacked instead of tabbed (pull one of the tabs down until they both pop out).
Increase size of "Pre-Comp Footage" (in Composition > Composition Settings).
In your "Original Footage," comp, make anchor point, position and rotation visible.
Alt-click on the stopwatch for each of those layers to see the expressions.
Pick-whip FROM "Original Footage," TO "Pre-Comp Footage." Link the following properties.
FROM Position TO anchor point.
FROM Anchor point TO position.
Rotation goes to rotation, and AFTER you do that, add the "*-1" to the expression on "Original Footage."
Once you've done this, you should have your footage reverse stabilized. Your subsequent adjustments for the demon face (or sunglasses, or what have you) should be don on the "Original Footage" comp. In the "Original Footage" comp, for example, you can bring in sunglasses on a new layer, and parent that layer to the "Pre-Comp Footage" layer. It will then inherit the motion values from the "Pre-Comp Footage" layer.
THE LIQUIFY FILTER
Effect > Distort > Liquify
You can keyframe the distortion percentage overall.
CHANGING COLORS
You can do this via an adjustment layer, which has a mask attached to constrain the effect to a specific part of the footage.
Layer > New > Adjustment Layer
You can apply a number of effects to the masked area – glow, color correction, etc.
Bonus link: Transformation scene playlist
