Do you know the gloves that turn into mittens by pulling a cap over the fingers? They can be nice and warm but the problem is that there are only two options: cap or no cap. Also, they're sort of ugly (especially when the cap is off and dangling on your hand). Therefore, I came up with these double-layered gloves, where the second layer rolls up or down over your fingers.
You can roll the second layer all the way up to uncover your fingers, all the way down and over your fingertips to create mittens, or anywhere in between. I ended up using the gloves a lot with the extra layer folded back slightly to reveal my fingertips (as in the second picture). The fold creates some extra warmth just where you need it. And since I used stretchy fabric, the fabric keeps itself in place however far I roll it up or down.

Sewing these gloves requires some sewing experience. This is mainly because the fingers require quite a bit of precision. The pattern itself is not difficult: you'll just use your hand as a basis for the glove and create a cylinder out of a rectangle for the second layer. Both layers are made of fabric with some stretch (like jersey), and I thought it was a nice touch to use different colours and a ribbon that brings the two colours together.

In the following nine steps, I'll show you what materials you need, how to make the pattern and how to sew the gloves.

Step 1: Materials

For this project you'll need stretchy fabric, such as jersey, in two colors. In my case fabric #1 was blue, fabric #2 was green. My green fabric was a bit thinner and more stretchy than the blue, which made it perfect for the top layer. Adding the ribbon is optional, but it's a nice way to cover the stitches of sewing the two fabrics together.
So, here's your shopping list:

50 cm of fabric #1 (jersey or some other stretch material)
60 cm of fabric #2 (jersey or other stretch)
50 cm of ribbon
thread

Step 2: Drawing the Pattern

We're going to need three pattern pieces: the glove itself, a separate thumb piece and the extra layer that goes over the glove. Assuming your hands are symmetric, you'll only need to draw up these pattern pieces once. So, here's how you make them:
The glove:

Draw around your hand on a piece of paper. Spread your fingers out a bit, in such a way that your index finger and that side of your hand (excluding the thumb) form almost a straight line (see image). Make sure you'll have about 0.5 cm of extra width for each finger. You won't need to add extra length at the fingertips.
Finish into a rectangle of the following width and length (this will be the length of the entire pattern piece, not just the rectangle part)
- width = measure around your knuckles (for me: 20 cm) and divide by 2 (so 10 cm)
- length = measure from fingertip to wrist (for me: 30 cm) and add 5 cm for the cuff (so 35 cm)

The thumb:

Mark off the tip of your thumb, the lowest knuckle and the bottom, where the thumb is attached to the wrist (see notes in image). These will indicate the length of your pattern piece (tip to bottom) and where the widest part should be (the knuckle).
Draw the shape shown in the last picture: heart-shaped at the top and round at the bottom, with the widest part at the knuckle with the following width:
- width = measure around the knuckle you marked (for me: 8 cm)

The second layer:

A rectangle with
- width = twice the width of the glove (for me: 20 cm)
- height = length of glove (for me: 35 cm) + length of the part that can be rolled back: measure from fingertips to just past your knuckles (for me: 15 cm)

Step 3: Cutting the Fabric

Cut the glove from fabric #1 as follows:

Fold the fabric along the grainline (have a look here if you don't know how to find the grainline) and put the index finger of the pattern along side the fold. In the image you see how the cut piece will look when you're done.
Cut out around the pattern, adding about 0.3 cm seam allowance. In between the fingers a seam allowance is of course not possible, but that's ok. Be careful not to make the tips of the fingers much wider than the rest.
Cut only one layer at the time, because that makes it easier to be precise.

Cut the thumb from fabric #1 with a seam allowance of 0.3 cm. The imaginary line from tip to bottom should be on the grainline. This pattern piece does not need to be cut on a fold.

Cut the rectangle for the second layer from fabric #2 with a seam allowance of 1 cm. The longest side of the rectangle should be on the grainline.

Step 4: Sewing the Two Layers Together

We start by sewing the two fabrics on top of each other, as follows:

Lay out fabric #2 with the right side facing the table and fold back (wrong sides facing) the length of the part that can be folded back (you measured this when making the pattern: from fingertips to a bit past the knuckles - 15 cm for me) plus a seam allowance of 1 cm.
Now lay fabric #1 with right side facing fabric #2, such that the fingers are on the double layer of fabric #2. See images. The wrist ends of both fabrics should match.
Secure with pins and stitch with a wide zigzag over the edge of the part that was folded back (see image): you'll stitch through three layers of fabric (two layers of fabric #2 and one of fabric #1). By using a zigzag you'll also prevent fabric #2 from fraying. Start and stop about 1 cm from the sides.
Optional: cover your stitches with a ribbon:
- Stretch out the fabrics slightly. The result (after stitching on the ribbon) will not lay flat (as you can see on the image), but once you're wearing the glove the fabrics will stretch and the ribbon will be back to normal.
- Lay the ribbon over the previous zigzag and use a normal straight stitch to stitch the ribbon onto the fabric.
- Again start and stop stitching 1 cm from each side. The ribbon itself should reach all the way to each side.

Step 5: The Fingers

Our next step is to sew the fingers:

Fold the fabrics with the right sides of fabric #1 facing each other. The glove will now be inside out. You'll need to fold away fabric #2 from in between.
Stitch the seams of all four fingers with an elastic stitch and a seam allowance of 0.3 cm. If your machine doesn't have an elastic straight stitch you can use the smallest zig zag (and set it to a short length in between stitches).
Try on the glove inside out (see image) and adjust if necessary.
Finish off the seams with a serger or with a wider zigzag.
Turn right side out (see image for the result).

Step 6: Finishing the Fold-back Layer

Before making the thumb, we finish stitching the two layers together. In this step, we start with the fold-back part above the ribbon. The result will be a cylinder that covers the fingers with no seams showing. This requires you to turn the whole thing inside out, and a little hand-stitching for the finish.

Take the outer layer of the fold-back part and pull it back over the ribbon such that you'll have the right sides of the fabric #2 facing each other (see image, where the pin marks where you start sewing).
Stitch (with an elastic stitch) almost all of the seam, but leave some (2 cm) for turning it all right side out (see image, which was already turned right side out). Finish off the seam with a serger of wider zigzag.
Turn right side out.
Finish the remaining 2 cm by hand.

Step 7: Finishing the Two Layers at the Wrist

In this step, we'll finish the two layers at the wrist: the result of this step will be an entirely finished glove except that it misses a thumb.... which we'll attach in our next step.
As for the two layers:

Turn the layers inside out (this actually means the wrong side of fabric #1 is facing the right side of fabric #2).
Stitch (with elastic stitch) the seam at the wrist end of the glove (see image). Finish off with serger or zigzag.
Turn right sides out.
The next part will be much like the seam in step 6: fold back the top layer (fabric #2) over the ribbon to make the right sides facing (marked with a pin in the image).
Stitch (with elastic stitch) almost until the end. Leave about 2 cm for turning the right side out. Finish the seam with a serger or zigzag.
Turn right sides out.
Finish the last 2 cm by hand.
As you can see in the last image, the ribbon still needs some work: fold the seams and the ribbon in and finish by hand. Try to make the ends of the ribbon meet!

Step 8: The Thumb

Last but not least, our glove needs a thumb! This is where you need to pay attention whether you're working on the left or right hand.

Put the glove on and mark the base of your thumb with pins (see image).
Take the glove off and cut out an oval shape within the pin markings. Tips:
- Be careful not to cut it too big! It's better to make it a bit too small first.
- Put on the glove to see if you cut it right (see image): if necessary, cut a little bigger.
Take the thumb piece, fold, and stitch (with elastic stitch) the seam of the heart-shaped top part. Try on the thumb inside out (see image), to check if it fits. Adjust if necessary. Finish the seams with a serger or zigzag.
Turn the glove outside in, and the thumb right side out.
Pin the thumb to the glove as shown in the image: with the right sides of the thumb facing the right side (outside) of the glove. If you've ever attached a sleeve to a shirt: this is very similar.
- The seam of the thumb should be at the top (closest to the ribbon) of the oval as marked in the image.
Stitch (with elastic stitch) along the oval to attach the thumb to the glove. Make sure you stitch through 3 layers: once the thumb and twice the glove (fabric #1 and fabric #2). Finish with a serger or zigzag.
Turn the glove right side out, and you're done!

Step 9: The Second Glove

Assuming your hands are more or less each other's mirror image, you can use the same pattern to make a second glove. Go through steps 3-8 for making the second glove. The only step where it matters which glove (left or right) you're making is step 8: be sure to try on the glove on the correct hand when marking the thumb!