hey, like the title says, how do you mute the strings when you are sweep picking upwards( towards the ceiling). when i sweep downwards im able to use my palm and it works perfectly, but when going upwards it seems impossible to use my palm.
its hard to master.
but after you go down with palm muting (however way you go down), and slightly twist your hand towards the ceiling so that the bottom of your palm can reach the strings as you hit them
hard to explain but. hope you understood

Ibanez RG350DX Electric Guitar With DiMarzio Tone Zone
Academy Electric Guitar
BeaverCreek Acoustic Guitar

Roland Micro Cube Amp
Academy 15W Amp
Peavey Vypyr 30
Peavey Sanpera Footswitch I
Might have to slide the heel of your pick hand muting the strings along with the sweep. That technique can be a pain in the ass if you've always done sweeps open, but sounds cool bridge p.u. As strange as it may sound, I have an easier time doing those cleanly if the action is slightly higher.
The exact same way you mute normally. Sweeping is just like playing a scale but it's usually just one note per string. The muting does not change, it's the sweeping action that changes.