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This row is referred to as the “home row” on your concertina. Keep your thumb outside of the straps and use your index finger through your pinky to control the keys on the concertina. If all your fingers cannot reach the keys, practice moving your fingers around to increase their dexterity. Each concertina will have a different layout for their keys depending on how many keys it has and the type you purchased. Refer to the owner’s manual or fingering chart to learn which keys produce the notes you want. Middle C is a good starting note, and on an English concertina, it is typically the key your second finger, or middle finger, rests on in the home row of your left hand. Start with middle C in one of the middle rows of the concertina. Depress the key and either open or close the bellows, depending on what position they’re currently in. The note you selected will play as long as the bellows are moving.  Name the note as you play it to familiarize yourself with the sound. This way, you’ll learn to play the concertina by ear. Find C1 on the opposite side of the concertina as middle C. Play C1 followed by C to hear the difference between the octaves. Look up introductory concertina videos to watch how someone else plays the concertina. These lessons will go over how to properly use and hold the instrument, basic notes, and how to play simple songs. Look for various videos online from different instructors.  Some lessons are usually free on sites like YouTube but will offer further lessons for a small fee on their website. Having a visual reference can be really helpful for beginners.

Summary:
Keep your fingers on the top 4 keys in the first row. Check which keys play specific notes. Press the key down while opening or closing the bellows to play them. Watch video tutorials for a better understanding of notes and placement.