This armband is a relatively easy project for someone who can handle a sewing machine and it requires about an hour of your time.
Step 1: Things You Will Need
etc. sewing stuff
The most difficult item to come by will be the reflective band. It is definitely best to get something stretchy, and the easiest thing to make this reflective MP3 armband out of are Army PT armbands. I actually got the idea for this instructable a couple of years ago when I was in the military and had a bunch of these things laying around. They are required whenever soldiers do physical fitness, so I kept losing and replacing them, but would eventually find them again leaving me with a couple extras.
If you can find the armbands in a military surplus store or online, then you can skip most of this instructable - it really simplifies the process because the armband is already half made!
Step 2: Measure and Cut
1. Measure the circumference of your arm, keeping in mind the thickness of your work-out clothing. [Mine is 31cm]
2. Measure the width of the velcro. [2.5cm]
3. Measure the reflective band to equal the circumference of your arm plus 3Xthe width of the velcro. [38.5]
4. Fold the reflective band to make it twice the length and cut. [77cm]
5. Figure out how wide the band needs to be to wrap around three sides of your MP3 player, with 1/8-1/4in (1/2cm) overlapping both sides. It should also be long enough to wrap 3/4 around the length of your MP3 player.
Step 3: MP3 Enclosure
2. Sew the top edge over about 1/8-1/4inch
3. Mark and cut the openings of the areas of the MP3 player/cellphone that you would like access to from the exterior of the armband.
4. Fold opening flaps over and sew around all edges.
Step 4: Sewing MP3 Enclosure to Armband
1. Decide where you want your MP3 player/cellphone to hang from your arm. I am right-handed, so I decided to put it on my left arm. I also was concerned about having the velcro go underneath my arm while jogging, so I made sure to pin the enclosure farther to the right - close to the side where I will sew the scratchy part of the velcro facing my arm (which I chose the folded edge for) .
2. With both sides of the armband folded together, sew the scratchy-sided velcro on the side that will be facing your arm. Since I designed mine to fit on the left arm, I sewed the scratchy-sided velcro on the underside of the far right. You can wait to do this step, but I suggest doing it now because it will make it easier to place the enclosure.
3. Make sure the armband is unfolded and pin the enclosure on the front layer that will be facingaway from your arm. Sew one side of the MP3 enclosure piece to one layer of the armband. Test the width of your MP3 player and adjust sewing as needed to make the phone fit snugly and evenly in the enclosure.
4. Pin and sew second side of the MP3 enclosure to the armband after determining it is centered and adjusted to the MP3 player.
5. Pin and sew bottom corner folds. Be careful to make the enclosure long enough or your MP3 player will stick out of the top.
6. Fold the sides of the remaining bit of the enclosure (the back side) in so that you can pin it to the front and sew them together along the sides of the enclosure. The end will be inside the fold of the armband, or, at this point, on the back of everything.
Step 5: Sewing Armband Layers and Velcro Together
1. Fold the armband layers together and pin. The ends of the layers should be tucked in so they don't unravel (on the left end of my armband) and the fuzzy-sided velcro should be pinned on top, ultimately facing away from your arm.
2. Make sure your MP3/cellphone enclosure's top end is on the same side as the open edge of the armband. Sew along the bottom edge and around all of the remaining velcro pieces, skipping the section attached to the enclosure.
3.OPTIONAL: Hand sew the enclosure portion to the back layer of the armband. If you do not there will be a small open section where coins could fall out, but if you are only carrying bills or cards this shouldn't be a problem.
4. Melt a hole for your headphone jack. First mark where the hole should be with a pencil, then apply heat to a pointy metal object and lance the fabric where marked. I first heated a seamripper, then decided that was too slow, so I used an old headphone jack to finish it.