Play a guitar with your left hand. I know a guitar seems complex to play when it comes to playing a song, but try stroking each string from top to bottom or vise versa. i believe you stroke each string with your thumb first, as i assume you are a beginner.

Lots of guitar are right handed, and the design of this exercise, can be done on those type of guitar. Just turn the guitar stick to the right, and play the string, as is.

You can strum with a guitar pick as well