1/2 yard – 1 yard fabric (depending on how high your boot leg is)
1/2 yard – 1 yard Thermolan Plus
2 – 4 sheets 12×18″ ultra stiff plastic canvas (depending on how floppy your boots are)
Cardboard boot insert from packaging (optional)
Clear ruler with grid
Fabric and paper scissors
Iron and ironing board
Sharpie or marker
Step 1: Trace the silhouette of your cardboard boot insert onto a piece of plastic canvas to make the plastic insert. If you don’t have a leftover cardboard insert from your pair of boots, trace the top of the boot down to the ankle to make a pattern. The purpose is to create a shape that will fill the leg of your boot when you’re not wearing it. Repeat this for the other boot, making a total of two plastic canvas inserts.
You may want to make a total of four plastic canvas inserts instead, two for each boot. This depends on the boot’s degree of floppiness. I used one plastic canvas insert for each boot in the picture above, but could definitely see using two each for my suede boots.
Step 2: Using your plastic canvas insert, trace the shape on to a piece of double-thickness Thermolan Plus. Cut out along the lines and repeat for the other boot.
You will now have a total of four Thermolan Plus shapes, two for each boot, and two plastic canvas inserts, as seen above.
Step 3: Using your plastic canvas insert as a pattern, trace the boot shape onto a piece of freezer paper. Add a 1/2″ seam allowance around edges using a clear grided ruler.
Step 5: Lay your Thermolan Plus pieces on top of the wrong side of your fabric, making sure to keep a 1/2″ seam allowance border. This allows the Thermolan Plus to not be caught in the seam allowances when sewing, making nice, bulk-free seams.
Peel back one side of your Thermolan Plus from one side of the insert fabric. Spray adhesive in a back-and-forth motion lightly over the exposed Thermolan. Smooth Thermolan back over to adhere to fabric, and repeat on other end. Flip fabric and Thermolan piece over and smooth out any visible wrinkles that may have happened during adhesion.
Repeat for other half of boot insert. You will have two boot insert components made of a piece of Thermolan Plus fused to the wrong side of the fabric.
Sew around boot insert with 1/2″ seams, backstitching at both ends to secure stitching. Clip corners.
Step 7: Turn boot insert right side out and press seams, making insert nice and flat. Doesn’t that look pretty?
Step 8: Insert plastic canvas into boot insert “pocket,” guiding it in with your hand. You may have to trim down the top of your plastic canvas a little so that a 1/2″ seam allowance of fabric can be folded over the canvas, seen in the next step.
Step 9: Fold in 1/2″ seam allowance over canvas and into “pocket,” forming a closed seam at the top of the boot insert. Pin in place through fabric and canvas.
Step 10: Using coordinating thread and a needle, stitch the top seam closed with a slip stitch. Bury knot and clip thread ends. The top of your boot insert should look like this:
Floppy boots, begone!