String crossings can be tricky, so practicing string crossings and crosspicking is essential in developing a fluid picking hand. There are two types of string crossings on the mandolin, assuming you’re using alternating picking: inside string crossings (where you play a downstroke on a higher string and an upstroke on a lower string) and outside string crossings (where you play a downstroke on a lower string and upstroke on an upper string). In Week One, Ethan gives you some basic string crossing exercises using open strings.