Fuck the bubble bags. Silk screen and dry ice.
You can get a screen from your local silk screen printers. You want a 110 mesh in a frame. They will probably have some old ones they will part with cheap. Tell them you need it for printing circuit boards.
You want your weed fresh, do not dry. If you will be trimming for days, put the trimmings in the freezer.
Use a big piece of glass. Tape something under each corner of the frame to keep the frame about a half inch above the glass. You want to have a nice big piece or glass to collect the keif with.
Mix weed and crushed dry ice, gently push it around on the screen. I use a lid from a pot to do this. Keep doing this until the kief starts to get a hint of green and then start over with more trim. You don't want it to be real green. If there is any doubt, press the keif with your fingers. It should stick together. If it does't stick you've gone too far.
When you have a bit of a pile, scrape it up and put it off to the side. This way you can see the color change easier.
When you are all done, use wax paper to press the kief into a block. Leave the block to air dry for awhile. You can smoke immediately but it will get better over time. A 50 gram block will dry to around 25 grams.
Why is dry ice better? When you are done, your trim will be mixed with dry ice. The dry ice will evaporate and won't add much in the way of moisture to your weed so you can easily dry it. After you have dried it, you can run a second extraction with either ISO, butane, hexane, pentane or whatever. If you use a bubble bag you will wind up with a pile of soggy shit and you will not be able to do the second extraction.
For the record, I invented the dry ice process and posted the original on OG back before they were shut down.