To begin with, get a fabric you like, and cut it to get a piece of 36-by-30-1/2 inches. From that piece of fabric you need to cut two piece of the size of 36-by-6-1/4 inches, and then connect the right sides of the fabric. Now, you need to flatten the fabric and the seams to pin the pieces into place.
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You need a thread to match your fabric. After you are done pinning the piece into place, all you need now is a large serving bowl, and place it on the corner of the piece, and make sure the side piece sticks out from under it. Use a pencil to trace the curve, and give shape to the fabric. Grab a pair of scissors and then cut along the line you just made, as you repeat the same for all four corners and then sew the narrower pieces with the wide ones.
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For this step you need a turning tool. All you need to do now is to make sure the cover isn’t inside out anymore, and for that snip and turn the corner. Use your turning tool to align the fabric at the seam. This will leave an opening, and for that you need to pin the edges to close it and then sew it closed.
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All you need is a ribbon, and when you cut some ribbon for your tent, the dimensions of the straps will vary because of the seat. Place the tent over the car seat, and the straps should run over the top of the handle. Mark the right place to stitch the straps, and then sew them to the tent.
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