Finally! The long awaited weighted blanket tutorial.
Here are the materials needed for making your blanket. How much fabric and how many pounds of poly pellets depend on the size of your finished blanket. For this blanket I used:
2 1/2 yards of cotton fabric (top of blanket)
2 1/2 yards of muslin (inner fabric)
2 1/2 yards of flannel (back of blanket)
8 pounds of poly pellets
thread
Wash your fabric in hot water and dry in the dryer. Iron fabric after drying.
Figure out the size of the pockets that will hold your poly pellets. This blanket was for a twin sized bed, so my final measurements were 40"x72". I like to have 2" around the edge of the blanket for seam allowances and ease of sewing. This left the available area for the pockets at 36"x68". Each pocket will end up being 6"x6" except for the top and bottom rows. These pockets will be 6"x7". I am not great with math so here is the fantabulous way I use to figure out each blanket.

Draw your grid on the muslin.

Lay the top fabric right side down and then lay your muslin on top with your grid facing up. Smooth out the two fabrics and pin, pin, pin!

Sew across the bottom of your blanket and then sew the up the columns. I like to start from the bottom and sew my way to the top to help prevent puckers.

Calculate the weight of poly pellets required in each pocket. This blanket weighed 8 pounds. I have a digital scale that measures in ounces and grams. I usually measure in grams because the math is a lot easier! Eight pounds is 3,636 grams. Divide by 66 pockets and you come up with 55 grams of poly pellets per pocket.

Measure 55 grams of poly pellets and pour them into the first column. Do this 5 more times until all of your columns are full.

Sew across the row closing your poly pellets into the pocket. Be sure to push all the poly pellets away from your sewing foot and needle. It is not fun when your needle hits a poly pellet. Continue weighing, filling and sewing across the rows until you reach the top of the blanket.

Lay your flannel right side up and place the blanket top side down onto your flannel. Be sure to smooth out the flannel as your lay the top down. This will prevent puckers and wrinkles.

Pin around the edges of the blanket leaving about 9" open on the bottom. This will allow you to right side out the blanket after sewing. Sew around the entire blanket and don't forget to leave the opening!

Right side out the blanket paying special attention to the corners. Sometimes I use the back of a spoon to poke them out.

Pin or iron around the outer edge of the blanket.

Sew around the edge of the blanket making sure you close the opening at the bottom of the blanket.

Viola! Your weighted blanket is complete! Snuggle up and sleep well!

Feel free to e-mail me with any questions. I will try to get back to you as soon as possible!
Disclaimer: I am not an OT nor do I play one in the bloggy world. The standard formula for a weighted blanket is 10% of body weight plus 1 pound. Always check with your OT to determine the proper weight for your blanket.