you can clean your stencil with just water and a stiff brush, like the one used for scrubbing dishes. Lay the stencil on
a flat surface like cutting board or baking tray and scrub it under
running water. Make sure to place a mesh into a drain hole, you don't want all that paint residue going down your drain. It's always easier to clean the stencil soon after you finish your project, as opposed to letting it sit for days or weeks. Depending on the paint used, it can come off very easily or
may need a slight pre-soaking to loosen it. Usually, acrylic paints come off very easy, and some latex paints may stick a bit more. We have a nice video showing how to clean a stencil, please check out our Video tab!
For removal of adhesive and stubborn paint, try
Dawn's "Power Dissolver" in a blue spray bottle. Not very easy to
find, but amazing product. Spray on your
stencil and clean as usual, or spray the stencil,
roll up very carefully or lay flat and place into a large plastic trash
bag. Seal. Let sit for a few hours or - better - overnight and then clean as described above.
You can also
sit brushes that have dried-out paint on them overnight, and
oftentimes you will have saved that brush.
Some other products work too, such as Motsenbocker's Lift-Off Latex Based Paint Remover, Simple Green and Krud Cutter. For adhesive removal, try Bar Keeper's Friend cleaner.
It's important to remember that it's very difficult to completely remove spray adhesive from a stencil, but we find that it is not necessary to get it off completely, the stencil still will be very usable for your next project even if it's a little bit sticky. Just make sure to store it on a piece of a wax paper or freezer paper, as a backing.