These two guitar chords exercises are featured in the book 50 Acoustic Guitar Chord Exercises
On this sheet, we start to work on strumming rhythms. Exercise 5 uses C and Am chords and the rhythm is down up down up down down. Exercise 6 uses F and Am chords and the rhythm is down down up down down. On the video I show you how to practice these using a metronome. You could use this sheet and follow this video for a quick 5 minute lesson on practicing the C, Am and F chords, which are fundamental to learn and practice on the guitar.