A really simple way to make your own stencil / mask is with a glue gun.
You need a glue gun, glue sticks and a craft sheet!
If necessary you can draw your design on a piece of paper and place it under your craftsheet. You can still see it lightly.
Then start tracing your design...
Wait untill it dries...
Once it is dry, you can peel it right off the sheet...
That's it... All done!
Ready to use...
These are some designs...
On the pictures: My Mam and Dad in the sixties!