Take off one string. I start with the 6th strings if I am changing all of my strings. Using a peg winder will make the process much faster and easier. Do not take off all of your strings at once, just one. There are times when it is necessary for certain repairs or maintenance to take off all of the strings. But if you are just changing your strings, change one at a time. This will help you with tuning the new string, and help you avoid making unnecessary neck adjustments. As you are turning the machine head (tuning peg) with the peg winder, make sure that the string is getting looser.

Depending on the style of guitar you have, you may need to cut off the end of the old string so that it will slip easily out of the guitar.

How you do this next step will really depend on your guitar. The guitar that I am using here is similar to a Fender Stratocaster. So I take the new string and feed the end through the back of the guitar. This is another reason that you will want to change only one string at a time at first. This way you can look at how the old strings were attached to the guitar. Assuming that they were put on correctly before.

Then pull the string through the other side.

Line the hole of the post so that it is facing straight down towards the neck of the guitar, then stick the end of the string through the hole. Pull the string tight so that there is not any slack in the string.

Measure approximately 1.5 inches (4 centimeters) past the post, and bring that amount of the string back through the hole. An easy guide to help you measure is this. If you have all 6 tuning pegs on one side, measure 2 posts past the one that you are working with. If you are stringing a guitar with 3 pegs on ones side and 3 on the other, measure a little bit past the next post.

By pulling the string back through the hole about 1.5 inches (4 centimeters) you now have the slack that you need to wrap around the post. You are now going to make on loop around the post with that slack. You will make that initial wrap clockwise for the tuning pegs that are on the left side, and counterclockwise for the tuning pegs that are on the right. This is with the guitar facing you.

Now cut off the excess string leaving about a couple of inches (5 centimeters). You don't want to cut the string off too short at first, just enough to get the excess out of your way for the next step.

Put your right hand 2nd, 3rd and 4th fingers under the string. You made one initial loop around the post, and now you are going to wrap the rest of the loops underneath that initial loop using a peg winder. You may find this easier if you are sitting in a chair with the guitar on the floor facing you braced between your legs. Or you can have your guitar on a table like shown here.

With your 2nd, 3rd and 4th fingers underneath the string, pull up so that the string is tight. As you are wrapping the string around the post you want to make sure that there is not any slack......keep it tight. Use your index finger to guide the string. You are now going to use the peg winder to wrap the string progressively underneath the previous wraps. Turn the peg counterclockwise for the those that face up, and clockwise for those that face down. For the pegs that face up you are going to have to wrap with your left hand, and hold the string with your right. You will wrap with your right hand and hold the string with your left when stringing up the pegs that face down.

When you are done, you can clip off the excess a little shorter than you did before you wound the string. You may also want to take your needle nose pliers and bend the excess string that is left down towards the guitar. This will avoid you grabbing your guitar and puncturing your hand. It will also help avoid shredding the inside of your gig bag if you have one.