A cotton/natural material for the inner bar (I used calico) - to make 3 required 300mm x 150mm
Covering material, such as fleece - for each one, I used 250mm x 120mm (each in a different colour)
Pearl Barley (around 100g for all 3)
Step 1: Making the inners
Take the calico/natural material. Fold it in half longways, and mark off into 3 sections, as in picture 2. Started 10mm from the end, then measure 80mm from that, leave a 20mm gap, measure another 80mm, a 20mm gap, and then the remaining 80mm, which should leave 10 at the end (the blue lines in the photo). The red lines are the half way points through the 20mm gaps, as a cutting guide for later.
Sew along the blue lines, to create little pockets in the fabric, and then, cut each section apart from each other.
Turn the pockets the right way around (seams on the inside), and half fill with barley. Turn over the top edge, so that the fraying is on the inside, and pin shut. Carefully sew this line, close to the fold. This should completely seal the bag.
Repeat the final step with all of the bags, giving you 3 sealed bags. These are the parts that will be heated.