Hey suga. To do a power shrug...
Have the weight on a convenient rack that is somewhere between knees and waist.
Lift weight off the rack.
Bend forward slightly from your hips with your knees flexed. Not too far but so you feel the weight load the back part of your traps. So you should be able to feel the pull on your traps going from just hanging str8 down to kind of high up on the backs of your shoulders.
Now when you explode up you do it like this,
All at the same time extend your knees, hips and shrug your shoulders up as hard as you possibly can and in your mind try to hold your shoulders up there.
Of course you should not be able to hold your shoulders up, if you can then add weight as you learn the lift.
Yep suga add weight to every lift.
Best regards.