Check the Mexican blanket to identify the back side -- some are so evenly woven you can hang them facing either direction. If there's a tag, knots, loose threads or other imperfections on one side, use that as the back of the curtain. Lay the Mexican blanket face down on a flat surface.
Attach a clip-on curtain ring at the top of the Mexican blanket. Insert a pin into the blanket to mark the clip's place. Remove the clip. Place a piece of seam binding or fabric hem tape along the top of the blanket at the level of the pin. Use a measuring tape or ruler to get the tape even across the top of the blanket.
Use a measuring tape or ruler to get the tape even across the top of the blanket. For example, if the clip grips the blanket a half inch from the edge, ensure the middle and end of the tape are a half inch from the edge. Iron the tape on the blanket using a low-heat setting to set the adhesive. Cut off the excess tape. The tape reinforces the blanket for the clip-on rings, to help the blanket hang straight.
Clip the rings to the top of the Mexican blanket. For a heavy, thick Mexican blanket, put the clip-on rings 2 to 3 inches apart. For a lighter Mexican blanket, put them 3 to 4 inches apart. Repeat the process of ironing on the tape and attaching the rings for each Mexican blanket. Hang the Mexican blankets on curtain rods over the patio windows.