My friend taught me how to use this and I am SOOOO addicted now it's so easy.
I use it constantly since it is so easy to make stencils with my Cricut.
So here's my best attempt at explaining how to use a freezer paper stencil.
First of all. Always make sure that the SHINY side is down. That is that side that will iron on to your fabric.
When making a stencil you want to keep all the "negative" pieces. If you were going to cut out a fish, you don't actually want the fish. You want the outline and "negative" pieces (the pieces you would usually toss).
A good tip is to first iron on the outline. Then when that is in place it will be easier to then add the inside pieces and iron those on all at once, or one at a time.
After you have it ironed on slip a scratch piece of paper inside your shirt so that when you are painting it the paint will not bleed through to the back (yes, I learn this the hard way!) :)
Then simply make sure you are using a fabric paint. They come in all sorts these days. There is normal to shiny, to matte, to glitter, to dimensional....
If you use regular paint it will stay on your fabric, but will make for a grainy look after washing.
You can buy a bottle of "medium" that can be added to a color of regular craft paint to turn it into fabric paint. I love the stuff, just didn't have any on hand to picture it. It can be bought at any craft store, or even Wal-mart.
I apply the paint right on to the fabric. Saves time, paint, and a mess.
Paint it evenly. Eliminate brush strokes. They can be visible, but usually after a few washes disappear.
Use a blow dryer to speed up the process. I am the most impatient crafter and usually end of botching my work due to lack of patience. The blow dryer and me understand each other! :)
When it's dry simply peel off the freezer paper and Yeah!
You can then do other layers, things....
Remember when doing words, you don't want the actually letters. You want the outlines and all the "circles" and such that are inside them. So make sure you don't loose them. I usually just keep them on my sticky cricut mat until I actually iron them on. This saves a lot of time.
You can go all kinds of crazy with this, but here's just some quick basic shirts I made for a family vacation: