After earning merit badges in the Boy Scouts, people usually sew the badges onto a sash, which is worn during formal Scout events. The sashes are wide enough to allow the badges to be sewn in rows of three across the sash and as many rows up and down as needed. Merit badges belong only on the front of the sash while the back is reserved for temporary insignia, such as patches received during a special event.
Cut an 18 inch length of thread and tie a knot in one end. Thread the needle with the un-knotted end.
Pin the badges to the front of the sash in horizontal rows of three. Depending on the rules of your troop, you can pin the badges in any order you want, chronologically or alphabetically. Sashes are worn from the right shoulder to the left hip. Make sure you're pinning the badges to the right side before proceeding.
Push the needle and thread up through the first badge on the top row. The knot in the thread should be on the backside of the sash. Move the needle over 1/8 of an inch and push the needle and thread down through the badge and the sash. Continue stitching all the way around the badge.
Sew several stitches in one spot once you've sewn all the way around the badge, then loop the thread through the stitch and make a knot. Trim the thread.
Cut a new length of thread, tie a knot in one end and thread the needle, then sew the second badge to the sash. Repeat the process until you've sewn every badge to the sash.
If you have enough merit badges to fill an entire sash, you will have to sew the extra badges to a second or even third sash. Only wear one sash at a time during ceremonies and events, though.