In one sentence, describe what the following article is about:

Hold your thumb and index finger parallel as if you were about to pinch something. Place the harmonica between the two fingers, pushing the left end inside your purlicue (the skin between the pointer finger and thumb). To properly play a harmonica, make sure its lowest note is on your left side. If the notes are not engraved on the instrument’s cover plate, blow on both ends to find which side is lower. To leave room for your mouth, make sure about half the harmonica is exposed. When blowing, keep your thumb and index finger back so you do not have trouble connecting with the instrument. While holding your harmonica, place your hands next to each other so they are straightened out with knuckles down. Move your right hand up so the tip of your left ring finger lines up with the tip of your right pinky. From this position, roll your hands together to create a sealed air pocket between your harmonica and palms.  Make sure to close large and noticeable gaps, especially at the back of your hands and around the harmonica itself. There is no way to make a complete seal using your hands, so don’t worry about tiny gaps. If your thumb is uncomfortable or you’re having trouble controlling the harmonica, try placing your right thumb in front of the instrument’s high notes. Just make sure to move it when playing on the upper part of the scale.

Summary:
Place the harmonica between your left index finger and thumb. Position the instrument so its lowest note is on the left. Leave the lip of the harmonica exposed. Cup your right hand around the harmonica to create an air seal. Place your right thumb in front of the harmonica for control or comfort.