This particular type of stethoscope cover is very forgiving. There are quiet a few patterns on the internet for free and good instructions. This is the one I went with for my customers, it's kind of several internet patterns, then I just did what I needed that I think works for the customers. I've sold over 100 at my store and so far (knock on wood) no complaints.
The following pictures were taken using a Brother SE350, it's a computerized machine, it's the first stethoscope cover I've made using it. I normally use my Kenmore, non computerized machine. Straight stitch and regular zigzag stitch are all you need.
Ok, materials - material 6.5 inches wide 30 to 34 inches long. I do mine 34. I I cut several pieces with these measurements that way they are laying there ready. Here's the material, a simple rectangle. Remember when using prints, that the stethoscope cover runs up and down. This particular frog pattern doesn't really matter.
I don't have a serger so I take each of the 6.5 inch ends and fold them down about 1/2 inch, then fold again 1/2 inch. This way the raw edge is well enclosed and won't be fraying. I do this to both of the thinner ends (6.5 inch ones)
Don't worry about everything being exact, have fun. You can iron this fold down and then you probably won't have to pin in place. Then I sew it in place using a straight stitch. I don't have an exact width, as I use the edge of my presser foot on these. It's about half way between 1/4 and 5/8. My needle is set to the left side, you do not have to do this. You want to sew it within a quarter inch of the folded edge (left folded edge in picture below). Do this to both ends.
Both ends should look like the above picture.
Now it's time to add the elastic. The first time I did this, it was a mess and didn't think I'd be able to do it. Now I hardly need to look. Some say you should zigzag stitch this, some say it doesn't matter. If I was using wider elastic, I'd definitely zigzag, but I'm using 1/4 inch wide elastic and just use a straight stitch. I basically line up the elastic next to my hem stitch I just did. The elastic goes on the bottom of the stethoscope cover, this prevents the cover from slipping down the head of the stethoscope.
I start the elastic approximately 1/4 inch from the edge of the material. When the long ends are put together, you don't need the elastic double up on top of each other. I hope this makes sense.
When I start sewing the elastic, I don't start pulling it yet. I anchor it down first, which do this like you start any stitch. Stitch a few stitches forward, then backward, then back forward. After that, I start pulling on the elastic. I pull the elastic and stitch at the same time. Do this very slow until you get used to guiding the material, elastic and pulling at the same time. This is where I had a heck of a time at first, I just kept doing it really slow, would stop a lot to be sure the elastic and material are where I wanted before they'd go under the presser foot. This is where I'm a bad teacher, I should have measurements, seam allowance, etc.
When I'm pulling it, the width of the elastic gets thinner, I don't pull it tight enough to where it's half it's original width. I pull it to where its pretty taught. I stop my stitching about 1/4 inch before I reach the edge of the material, then backstitch. Cut the elastic off after the stitches stop.
This is the elastic part after it's been sewn.
Now it's time to sew the side. Put right sides togther. Line it up nice and even and pin in place. I start sewing at the top (no elastic side). I sew with almost a 5/8 seam. I actually use a zigzag stitch here to help prevent the material from fraying. Then I sew a straight stitch along the inside edge of the zigzag stitch. Sew from the very top of the cover to the very bottom. Be sure to do your backstitching at the top and bottom.
First picture is the right sides together at the top hem of the cover.
If I have a lot of edge, I will take the pinking shears to neaten up the seam. You don't have to do this.
The top of the cover needs something to hold the top up so it doesn't slide down the stethoscope. I've always used velcro. I now have the tool to do snaps. To do the velcro, I used the half inch wide velcro, be sure to get the type that doesn't have the glue/sticky stuff as this stuff gums up a needle really quick. I cut the velcro about 3/4 inch long. The at the top of the cover, inside, sew a piece to each side to where it can velcro together to keep the cover from sliding down. I now am doing the snaps, basically because its a few minutes quicker.Thats about it. Feel free to ask me any questions or to help clarify anything. This is by far thefirst real tutorial I've ever done.