Flat-panel curtains do not have a header tape. These curtains may use many types of attachments, such as grommets, rings and clamps, tabs or pockets. The curtain itself is just a simple, flat panel that is hemmed and ready to use. Often a pocket is sewn into the top as a default way to hang the panel. If you use heavier fabrics with good draping qualities, you will not need to sew a liner into your curtains. This will make crafting your panels even simpler.
Measure the width of your mounted curtain rod. Add 2 inches. Measure the height from the top of the curtain rod to the floor. Add 6 inches for hems. This will give you the measurement for one curtain panel. Your window will need two of these panels to cover the window with a nice gather at the top.
Cut your fabric to size, using scissors.
Turn the side edges under by 1/2 inch and then under again by 1/2 inch. This makes a double hem and hides the raw edge. Sew the hem on both sides, using the hem stitch on your sewing machine.
Fold the top edge under 1/2 inch and sew. Fold the top edge under 4 inches and sew the sewn edge to the curtain, using the hemming stitch on your sewing machine. Turn the bottom edge of the curtain under 1/2 inch and sew.
Hang your curtain panel on the rod. Pin the hem so that the length just breaks against the floor. This means the fabric will touch and just start to bend. Sew along the sewn bottom edge, using the hemming stitch on your sewing machine.
When making your curtains, consider using two colours of fabric for a more custom look. Often designer curtains will have a second colour of fabric in the lower 18 inches of the curtain. Seam the two fabrics together and sew all panels for one window at the same time so that the colour changes line up neatly.