How to Palm Mute on an Electric Guitar

Listen how palm muting sounds with a distorted guitar:

To perform palm mutes place the heel of the palm of your picking hand near the spot where the strings go into the bridge, you can slightly press against the strings to get sharper tone and decrease the sustain farther:

Muffling Strings for Performing Palm Mute Technique

Now play your theme while keeping the palm of your hand in that position:

Playing Palm Mutes
And that's all there is to it!

In printed guitar tabs palm muted notes are marked as P.M. characters over the lines representing the strings:

Palm Mute Notation in Guitar Tabs

In plain text tabs palm mutes also can be marked as the "x" character that precedes a fret number: