I think it was Sevarn who mentioned somewhere that he likes to enter a TGS,and visualize that a crust is forming over his hand,morphing it into a draconic claw.This is Shapeshifting101.ANd that with each breath,the transformation is solidified.
Then,he would look at his victim and imagine them as this big fluffy thingy,this buzzing mass of energy,that’s been made solid as he breathes it.Then,he would swing his dragon hand(his left hand),and visualize that aura being poked,as a hole is made in it.
And that one by one,he could take down chunks of energy.
When feeding on someone who’s energy you really don’t want in you,you can filter the bad stuff out.As you pull it into yourself,visualize around yourself a filter,a giant sheet of energy that has these holes in it,through which energy could pass,but negativity is repelled.
Imagine this on your tendrils,or on your hand,if you’re feeding by these methods.
Also,I once remember using a method,where I would gaze at the person and see all the swirling energy around their aura,at which point I would envision it spinning around them.
It would spin,like a tornado,devouring their astral body.Then,as tornado would spread,it would begin to tear the person’s walls,and their defenses.And visualize that just increasing,and when you’re done with that,when you feel like you’ve torn the person right open,in slow and long inhalation,pull the resulting energy into yourself.
Those are some methods that come off the top of my head.