i made this mat out of the scraps of the canvas drop cloth i got a while back...i still have so much left to use!!
-iron on vinyl (and iron of course)
i wanted my mat to be 15'x12' so i cut 2 rectangles 16"x13". i looked up some animal silhouettes on google and traced them on to freezer paper-if you're cool you can print them, otherwise you'll just have to free hand them like me. cut out your freezer paper stencil and iron onto your mat (along the bottom of the 12" edge). once your stencil is ironed in place, you can start painting. make sure the paint is completely dry before peeling the freezer paper off. this was my first attempt at freezer paper stencils and i was pretty impressed by the clean edges.
next-iron on vinyl. i actually bought this like...2 years ago?? and i'm just now using it...it was kind of an impulse buy at the time but it's proved itself useful. anyway, i found it at hobby lobby but i haven't seen it anywhere else, not that i've been actively looking though.
cut 2 pieces of vinyl that are the same size as your fabric-for me 16"x13". fortunately the paper backing has gridlines so they ended up straighter than my actual fabric lol. next, following the instructions that came with the vinyl, you want to peel the paper backing off the vinyl. then set up a little fabric/vinyl/paper sandwich, so top down:
-paper backing (the instructions didn't specify but i put the shiny side down and dull side, with the grids, up)
-vinyl (sticky side down)
-fabric (right side up)
don't forget the paper-i definitely tried to iron the vinyl on without the paper...let's just say it did not work out well... also, i'd use a lint roller on your fabric prior to putting the vinyl on. i noticed afterwards that i actually trapped a couple hairs and a piece of hay in my mat...
moving on...iron, iron, iron...with lots of pressure. the instructions say medium pressure, but i'd put as much pressure as you can-i went over mine several times just to be sure. and repeat for the other piece of fabric.
now take the 2 pieces, right sides together, and sew down the two 16" sides forming a tube. flip right side out, press the open edges in, and top stitch all the way around. and your produce mat is ready to use!!
i didn't bother using any interfacing for this project because putting the vinyl on both pieces makes it a pretty thick mat. however, my fabric was canvas so if you are using something pretty thin i'd recommend using some interfacing just for some added structure.
i didn't have any problems with the vinyl sticking while sewing, but i read somewhere that if you put 2 pieces of scotch tape (i'm guessing the matte kind) on either side of the left side of the needle it helps the vinyl from sticking.