The construction of this scapular is very simple. In order to function as a brown scapular it needs to be pure brown wool. So, I cut four pieces of wool felt and embroidered an M for "Mary" and a cross underneath on two of the pieces. Then I measured a length of black embroiderey floss on my husband so it would be a comfortable length. I knotted the floss every so many inches (you can tell I kinda "winged" it, LOL) and placed the end pieces of the floss so they are parallel between two pieces of felt ~ one embroidered and one not embroidered ~ and stitched around the rectangle. Then I took the other two felt rectangles ~one embroidered and one not~ and found the direct opposite side which would be the middle of the length if it were still in a straight line. I didn't bother cutting it but sewed the two pieces of felt over the "u" so that the floss is parallel again. After stitching it around your scapular is "good to go"!
The tradition of the scapular was taken from religious who wear a scapular which is a long piece of fabric which is placed over the head and hangs down the front and down the back. I have included my St. Teresa of Avila as a visual aid. Although it started as a practical piece of clothing, it has come to symbolize consecration to God. Likewise we, the laity, wear our scapulars as a sign of our consecration to God. A priest or deacon "invests" the lay person in the Scapular Confraternity. The devotion to the brown scapular comes from the apparition of Our Lady where she conferred the brown scapular to us saying: "Those who die wearing this scapular shall not suffer eternal fire". This cannot be taken supersitiously or magically but just a promise that those who seek her aid she will lead to her Divine Son. The scapular is a way of life not a ticket to heaven.