Watch the JAM: Using Further Extensions online guitar lesson by TrueFire from The Indispensable Toolbox for Guitarists
JAM: Using Further Extensions - Chords and Rhythm Demonstration is a video guitar lesson presented by Susan Mazer and is sourced from Hands On Guitar: Beyond Beginner.
Just like the last tune, practice the strumming pattern using one chord until it flows. Then, practice the chords separately with just a down strum until you know them without looking at the chart. Finally, put the two together.