Let me start by saying that the Taggies Brand blankets are protected by a patent and they may not be created for resale. I've heard that the Taggies people prosecute those who try to sell their patented products.
Choose ribbon that coordinates (or contrasts, it's your preference) with your fabric. For my 12 inch squares (this will be the approx. finished size) I like to use 5 ribbons per side. Be creative - use different colors and textures. I use various widths of satin and grosgrain ribbons, and also something that looks almost like a wide flat shoestring/drawstring type material (I'm not sure what it's called.) I've even seen ric-rac used.
Cut the ribbon into 5 inch strips. I use the first ribbon as my cutting guide for the rest of the strips to save time. Then figure out the placement onto the blanket. I like to be sure I have a satin on each side and a wide ribbon on each side. I start with the middle ribbon placement and work my way out to the sides. Leave at least one inch between the ribbons and the sides of the blanket.
Next, fold the ribbons in half and pin them between the two fabrics with right sides of fabric together. The ribbons should be pointing inward toward the center of the blanket. This seems odd if you've never made a blanket before. But in the end, you'll see we flip the blanket inside-out to incase the seams. Trust me, it works.
After all the ribbons are pinned, put a row of extra pins marking a 3 inch spot on one of the corners which will not be sewn. This step can be omitted, but don't forget to leave this spot open. (I always get busy sewing and forget! The pins remind me.) This is the hole we'll use to flip the blanket inside-out.
Now, start sewing. I like to use a 3/8 in. seam allowance. That's about the width of my presser foot, so it's easy to follow. But use whatever seam allowance you're comfortable with, just keep it as consistant as possible. Before you start sewing, do a couple of backstitches to lock the threads. (this keeps the threads from coming undone.) Straight stitch right on top of your backstitches.
Pause when you get to the pins, removing each one as you sew. (I have a friend who just sews straight over her pins and rarely breaks a needle. I tried this once and kept breaking needles! I always remove my pins as I sew.)
When you get to the corners, stop sewing - leaving your seam allowance before reaching the end of the fabric. Lift your presser foot and turn the fabric so you can sew the other side.
When you get to the row of pins, stop and backstitch a couple stitches to lock the threads in place. Now remove the blanket from your machine and trim your loose threads where you started and ended. Remove the pins, there will be one loose ribbon that you need to set aside and attach later.
Trim the corners, being careful not to cut your stitches.
Find the hole in your fabric, and pull the entire blanket inside-out, through the hole.
Insert a closed pair of scissors into the hole and use the tip to make your corners have perfect points. (There is a tool you can buy to do this if you're afraid you'll rip your fabric. I haven't needed one. Just be careful!)
Now tuck the raw edges of the hole inside the blanket, being careful to keep the edges straight across the top of the blanket, and keep the corner squared. Iron the seam into place, and iron the rest of the blanket being sure not to touch the iron to the ribbons - they will singe! I learned this the hard way. I pull the ribbons out slightly as I iron to keep the seam from being puckered or wrinkled.
Get the last ribbon and pin it into place. You can either stitch the hole closed by hand or use your machine.
I like to use my machine. Keep the stitching as close to the edge as possible, remembering to backstitch at the beginning and end.
If you use a coordinating thread, it isn't very noticable.
Now, change your needle to a topstitching needle (it's okay if you don't have one, use the largest needle you have on hand. You can even use the needle you've been using, but the results will be a little nicer with the topstitching needle.)
This step can be omitted, but it makes the item easier to launder. On either side of the blanket, start in a corner and stitch all the way around the blanket using your desired seam allowance. Remember to backstitch at the beginning and end. Iron one last time.
One done, and one more to go!