To play a basic C7 (also called a "C dominant seventh") chord, start by placing your:

Now, strum strings five through one, taking care to avoid hitting the low E string.

This C7 shape is a little trickier to play, as it requires you to "barre" your first finger across multiple strings at once. The shape is referred to as a "barre chord," and you're going to find it challenging to play at first. Here's how you go about playing this C7 barre chord shape.

Slightly bend your first finger and lay it flat across strings five to one at the third fret.

Roll your finger back slightly towards the guitar headstock, so that the side of your finger is just starting to come into contact with the strings.

Place your thumb in the middle of the back of the guitar neck, approximately underneath where your first finger is on the surface of the fretboard.

Gently apply downward pressure on the strings with your index finger while also exerting a small amount of upward pressure on the back of the neck with your thumb—you're essentially squeezing them together slightly.

Place your third finger on the fifth fret of the fourth string and your fourth (pinky) finger on the fifth fret of the second string.

The hardest part of playing this chord is keeping your first finger pressed tightly against the fretboard—it is responsible for holding down notes on the fifth, third and first strings. Often, at first, you'll have a hard time getting all those strings to ring clearly.

Strum the C7 chord, being sure to avoid the open low E string. Don't be surprised if you only hear one or two notes ring. Try playing each string one by one, identifying exactly what is and is not ringing clearly. If you encounter a string that isn't ringing, adjust your fingers until you get it sounding right, then move on.

Here is a different way to play a C7 chord—a barre chord shape with root on the sixth string. The shape is similar to that of a major barre chord with root on the sixth string—you just need to modify that shape by taking one of your fingers off the fretboard. If you look at the shape and imagine that the barred eighth fret is actually the nut, the rest of the chord resembles an open E7 shape.

To play this C7 chord shape, start by slightly bending your first finger and laying it flat across all six strings at the eighth fret. Next, roll the finger back slightly towards the nut—similar to what we did for the C7 barre chord shape at the third fret.

Next, place your thumb in the middle of the back of the neck, underneath your first finger

Put downward pressure on the strings with your index finger while also exerting a small amount of upward pressure on the back of the neck with your thumb.

Then, start placing your other fingers on the guitar. Place your

... now strum all six strings.

Your first finger is doing most of the work here—it's responsible for playing the notes on the sixth, fourth, second and first strings. It's probable that when you first play this chord, you won't hear many strings ringing clearly. Don't get frustrated—go through each string one by one, ensuring it is ringing clearly. If not, try adjusting your hand position slightly until you can get the note to ring, then move on to the next string.