to palm mute a lot of strings i generally use the side of my hand and sumtimes my little finger... just make sure u place it very close to the bridge so that the notes u play r actually heard.

this is what i use for the intro riffs in call of the ktulu by metallica even tho its played with downstrokes... i just learnt it with alternate picking and stuck with it...

n e way...
ill cyas l8a!