I used some cotton bags I bought at the Swedish place (you know which one ...). I washed them before hand to get rid of any treatment still sticking to the fibers.
Bag 1: a stencil I bought years ago. I used a coppery color with a bit of sparkle.
Bag 2: easiest of the lot, really. I used toiletpaper rolls, folded them a bit to get a heard shape and dipped the ends into the paint. The yellow paint was a bit on the thin side, but I don't think it's a problem.
Bag 3: I uses some rubbery material which I cut into shapes and glued to a piece of pipe I've got lying around. After one round, the color was almost all used up, so I filled out the last bits with a brush. I think it would be better with a longer piece of fabric.
Bag 4: For this one, I wrapped some course twine around a bit of rubber and used this as a stamp. Fun, easy and I love the effect it creates.
Bag 5: Here I used masking tape to create a simple stencil. After each round of paint, I let it dry, then moved the masking tape to open up another bit. This one took the longest, but I really like the result.
Finally, I iron them all for a couple of minute with the iron set to hot. Hopefully this fixes the paint. I use a couple those bag for potatos, onions, ....
Great fun, need to get more bags to try some more.
I still get plenty of ideas.