Downstrokes: The Foundation for Strumming Chords
To play a downstroke strum on your guitar, raise your hand so it's just above the 6th string on your instrument and drop your hand down through all of the strings. Gravity's pull on the weight of your hand should propel this movement and you shouldn't being forcing your hand down through the strings. It doesn't need to be loud at this point and you just want to focus on the correct movement. Repeat this strumming movement a few times and watch the lesson video below to see a demonstration.
Use the tab below as a rhythmic reference. Whenever you learn a new technique, it's good to practice it with a metronome or jam track to keep you in time.