1.
Use your wire wrapper (pictured) to loosen the Low E-string. Remove the string from the tuner and bridge and discard it. (Be careful with the tight end of the string).
2.
Pull the new string through the bridge and pull it firmly down to the tuner’s string post.
3.
Maintain the tension on the string, loosen the string around the string post (counterclockwise) once or twice, and then pull the string through the hole in the string post. Pull the string tightly and bend the string downwards and at the right angle where it comes out of the string hole.
4.
Take the string up to the pitch and repeat these steps to the A and D strings (These are the wound strings).
Regular strings – The process for the simple strings is exactly the same, except that they require more turns around the string post. Instead of just inserting the string around the insert once, wrap it between 3 and 4 times. Then take the string up to the pitch.
6.
Once all the strands have been replaced, use your wire cutters to cut the ends of the strands a few millimeters from the strip of post.
Tips and warnings
When the time comes for one of your strings to snap unexpectedly or your strings get old and warn, these instructions will be helpful. There is no need for you to take your guitar to a store to pay someone to change your strings when you can easily do it yourself in no time!
Source:danspela.com