At home, I sit on the couch, the right side kind of in the corner. I find that sitting catty-corner makes it easier for my hands/arms to move. (I'm an english knitter/thrower).
On the bus, I sit with my project bag to my right and pretty much sit upright on the seat. I don't kint at a table very often but when I do, I have to have my chair back from the table so I can move.
I can't knit laying down because I'd probably fall asleep and impale myself on the needles.