Summarize the following:
Lay out your fabric so that it is in two layers and place your unfolded jeans on top of your fabric. Smooth them out so that they are flat and even. Then, trace around the edges of the jeans leaving about ½” (1.3 cm) on all sides for seam allowance. If you want baggier overalls, then trace further away from the edges of the jeans. For example, you could trace 2” (5cm) from the edges of your jeans for baggy overalls. You might also use a baggy pair of jeans to make it easier to get a loose fit. After you finish tracing around the edges of your jeans, use a sharp pair of scissors to cut along the edges of the lines you created. Make sure to cut straight even lines in your fabric. The 2 pieces you cut out will be the legs and waistband of your overalls. Next, you will need to create the bib pieces for your overalls. To do this, measure from your waist to your chest and cross the front of your chest. Then, add 1” (2.5 cm) to each measurement for a seam allowance. Trace a rectangle with these dimensions onto your folded fabric and then cut it out from both layers. These pieces will be the front and back bib pieces for your overalls. To make the straps, measure from your chest to your shoulder blade and add 1” (2.5 cm) for a seam allowance. This will be the strap length that you need to create. You can make your straps as wide or as narrow as you like, but 2” (5 cm) to 3” (7.5 cm) is a good size. However, make sure to add 1” (2.5 cm) to your strap width as well for the seam allowance. When you have determined your strap measurements, trace these onto the folded fabric and cut along the lines to make two identical straps. If you would like to include a pocket on the front of your overalls, then you can also make a pocket piece. To make a pocket piece, draw a rectangle onto your fabric and cut it out. Make sure that the rectangle is smaller than your front bib piece, but large enough to use as a pocket.  A good pocket width might be 4” (10 cm) by 6” (15 cm). Make sure to add 1” (2.5 cm) to both sides of the rectangle for the seam allowance as well. You will only need 1 piece to create the pocket, so you only need to cut out 1 rectangle.

Summary:
Trace the outline of your jeans onto your folded fabric. Cut along the lines you traced. Cut out 2 rectangles large enough to cover your chest and abdomen. Cut out the straps. Make a pocket piece if desired.