Sawyer Mini Water Filter - sit on it... the dirty water bag, that is. Works for me. YMMV.
I've been using an Evernew 2 liter as my dirty water bag screwed directly into the filter, with a short length of tubing (I wanted a little more length than the included "straw") going from the filter to my clean water bottle with a simple barb-to-bottle cap adapter (e.g. part of the Sawyer inline Adapter).
I put my weight on the bag slowly, by using my arm(s) to support some body weight and kinda lean into it gradually. I'm also careful to have a softish place for the bag to lie on, with no sharp points.
My evolution with the mini began with immediately rejecting the squeeze idea; I didn't find that a huge step forward from pumping a normal filter. Roll/squeezing like a toothpaste tube was an improvement, but still too much effort for me. Rigging it up as a gravity filter was close to happy solution; others have described that. OK, but I wasn't completely happy with the fuss factor, and there's not always a branch to hang from when you need one.
So one day I just sat on the water bag, watched the pretty waterfall I had stopped at for a couple of minutes, and my life was changed. I realize the bag probably isn't spec'd for that kind of pressure and will fail at some point, but I'm going to continue, and find out about how long that will take. I'll let you know.