Step 1: Cut out 2 rectangles of fabric that measure 7 3/4 inches by 8 inches.
Step 2: Fold one of the rectangles in half length-wise (it should measure 3 7/8 inches by 8 inches). Pin the sides. If you are using two different fabrics, this will be your outer fabric.
Step 3: Sew a half inch seam along each side (top remains open).
Step 4: Trim the edges to 1/4 inch and cut off the corners. This will reduce bulk and make your envelope look much more professional and neat.
Step 5: Repeat steps 2 through 4 EXCEPT on one side seam, leave about 2 to 1 1/2 inches open at the folded edge. It is difficult to see in the picture below, but my fingers are marking my open area. This fabric will be your lining if you are using two different fabrics.
Step 6: Turn the out fabric right side out. Push out the corners and iron well. Place the outer fabric inside the lining so that right sides are facing each other.
Step 7: Line up the side seams and pin. Match up the raw edges along the top and pin also.
Step 8: Sew a 1/2 inch seam all around the top edge. Be sure to back stitch where you start and stop sewing.
Step 9: Trim top edge to 1/4 inch from seam.
Step 10: Reach through the opening in the lining and pull the envelope all the way through.
Step 11: Fold the raw edges of your opening inward and pin.
Step 12: You can opt to do two things here. The most professionally thing to do is to slip stitch the opening closed. If small stitches are used, someone could almost never find your opening. If you are making this for your self, you can simply use your machine to stitch very close to the edge of the fabric.
Step 13: Push the lining into the outer fabric and iron.
Many people has asked how well the money fits into the envelope. Well, here it is. There is a good 1/2 inch on either side of the money and almost an inch at the top. I have never had a problem with my money slipping out so I do not put a closure on my envelopes unless a customer requests one. You can always add a small square of velcro to the top if you choose.
My hope is that this tutorial is easy to understand and useful to a great many! May you always have money in your envelope!