How do you hand mute on a guitar?

Just rest your fingers over the strings that need to be muted.

There are two basic methods to mute a guitar.

Palm muting is generally used to create a thumping or thick tone. Examples are easily heard in songs such as "Animals" by Nickelback, or "Every Breath You Take" by Sting.

The other type of muting, variously called string muting, chord muting, or just muting, is typically used to cut a chord short. That is, to create a burst of sound that suddenly ends. You can hear examples on songs like "Getting Better All The Time" by the Beatles, or "Life Is A Highway" by Rascal Flatts.

As you've already discovered, both styles are frequently used in Rock, as well as Country, for up-tempo songs. Each method can be used very effectively to emphasize the beat.

To Palm Mute you use the cushioned part of the side of your your strumming hand (the pinky side of your hand) to press down on strings where they meet the bridge. If you move your hand onto the bridge more, the strings ring more. If you move you hand further up onto the strings, you get more of a thumping sound.

To string mute (which works best with power chords or barre chords) simply release the pressure in your fingertips (on the fretboard). You control how much muting by how much pressure you release. You must keep your fingertips in contact with the strings, though, or they will ring with the open note.

For a more detailed answer, see my source:

Two kinds of muting - palm muting means that you rest the edge of your palm across the strings while you're strumming to dull the sound. Left-hand muting involves placing your fingers across the strings without pressing them down to the fret, and playing this way will give you a sort of "click" instead of the actual note. You should use more than one finger to keep natural harmonics from coming through.

It's called palm muting............While strumming you light place your hand an the strings, usually on the bridge, the harder you push the more muted it gets.

you need to keep your picking hand on the strings while you are picking. i am learning to do that in my guitar lessons. You can't press down to hard though just press down enough to get the effect.

Do you mean silencing all strings at once?,Just place open hand over the strings(palm the strings all at once).

don't press hard on the fret, but don't let go of the string?

hold all the strings down

Just don't play the X's.