Step 1: Drawing the Rim Shape
1. Using a hat that you have lying around, line up the inside edge of the rim with the edge of a piece of paper, and trace around the curve.
2. First, draw a vertical line from the center of the curve, down to the edge of the paper. Then, measure the width of the thinnest point of the rim using a ruler and draw the midpoint on the line.
3. Then draw a curve connecting the midpoint to one of the two points where the original curve meets the edge of the paper.
Step 2: Making the Shape
4. Cut along the larger curve to get a half-circle shape.
5. Fold the half-circle in half, along the vertical line, and cut along the second curved line you drew to make sure that both sides are equal. You should end up with a shape that looks kind of like a smile.
6. Next, trace the shape onto an old composition book cover and cut it out.
7. Cover the shape with duct-tape to make the shape stronger.
Step 3: The Rim Fabric
8. Take out an old sweater, cut off the arm and cut along the seem for a flat shape.
9. Trace two brim shapes onto the sweater, and cut them out about a half-an-inch outside the outline. Make sure you don't cut along the inside curve, just cut a straight line across the two points.
10. Place the two shapes right-sides-together and pin along the curve.
11. Sew along the pin line and turn right-side-out.
Step 4: Finalizing the Rim
12. Insert the brim into the pocket and stretch out the fabric out so that the seem ends up at the bottom half of the brim.
13. Pin along the inner curve, and sew along your pin line.
Step 5: The Beenie Shape
14. Take out the body part of your old sweater, cut along the seems. You only need one half of the body part of your sweater.
15. Fold the fabric in half, along a vertical axis, so that the right-sides are together and pin.
16. Measure and mark 10 inches from the fold. From the middle of your initial measurement, measure 8 inches up.
17. Sketch out a dome shape connecting the 2 end points of your measurement to your 8 inch measurement.
Step 6: Finalizing the Hat
18. Pin along the outline and then cut out about half-an-inch outside the outline.
19. Sew along the pin line and cut off the excess fabric. Make sure not to cut along the bottom edge, thats the hole that your head goes into!
Step 7: Attaching the Rim to the Beenie
20. Attach the rim to the hat by inserting the rim into the beenie so that the bottom of the beenie hem overlaps the inner curve of the rim, and pin together. Make sure that you pin the rim so that the edges of the rim are centered in between the seems of the beenie, so that the seems rest on the sides of the hat.
21. Sew together following your pin line, and sew another seem about an inch up to hold the flap down.
22. And thats it! You have an awesome new brimmed beenie hat!