This copper cuff is a fun piece of jewelry in and of itself, and makes a marvellous (and accurate) accessory piece for a variety of historical costumes.

*WARNING! WARNING* DANGER WILL ROBINSON!
Yes, there are tools used in this instructible. Yes, there is sharp metal in this in structible. YES, use extreme caution when working with tools or metal of any kind, you CAN injure yourself.

Ok, with THAT out of the way...

Step 1: Measure and Cut Copper Tube

If I am having to explain to you how to measure your wrist... *sigh*
If you don't have a fabric tape measure, you can wrap a piece of string round your wrist, and measure that. This is the length of tube you need to cut for your cuff. Mine was a bit more than 8". A hacksaw works well to cut the tube. If you have a tube cutter, I would recommend that for this step. It makes later steps much easier. I couldn't find a hacksaw or a tube cutter (though I own BOTH) so I used an angle grinder to cut it. The diameter of the tube will determine the width of the cuff. If you look above the vise, there is a LARGE copper cuff from a 2" tube in progress.

Step 2: Cut Tube Open

I use aviation snips for this part. A cutoff wheel or other such would work as well, but the idea is the same. (There are several instructables on how to make flat sheet from tube, should you like to try another way of it). When cutting wit hthe snips, one edge will curl inward, making it difficult to continue cutting. DO NOT use a single pair of pliers and your hand to open the cut wider. You WILL cut yourself. Keep cutting all the way to the end. The cut may get a little shaggy on the edges, but that's ok, we'll deal with this later.

Step 3: Flatten Tube Into Flat Stock

Find a nice hard surface to hammer the copper on, this will be the anvil. In a pinch you could use the sidewalk, but it WILL pattern the copper with the small irregularities on the pavement.
If the end cut has been spread open wide with the pliers, the tube will flatten easily. Just keep moving up the length of the tube as the part that you are hammering flattens out. Be sure to turn over the sheet as it flattens to get the edges as flat as possible.

Step 4: Trim Sheet Edges to Shape

The edges of your plate will be a bit jagged and sharp. Draw parallel lines on the plate as close to the long edges as possible. Use snips to cut the edges along the lines drawn to something far more smooth and less likely to shred you. Be sure to clip off the corner so that you will be able to make a smooth curve later.

Step 5: Bend Copper to Shape

Get a large diameter piece of steel or iron tube for your mandrel. Using the soft faced hammer, start to bend the very edge of the bracelet. Use sharp overlapping strikes along the width of the copper to start the copper curving. It will look much smoother when you are completed. Once the copper has a bit of curve, take the metal in hand and manually put a sharper curve in the metal simply by carefully bending it. This is a great deal quicker and much easier. From there put the curved copper (now very MUCH like a cuff) on the mandrel and hammer smooth and symmetrical any parts of the bracelet that look out of place until it all looks right. Or at least, right enough to you.

Step 6: FINISHED!

The bracelet needs some filing with a very fine file to clean up any weird spots or rough bits. This is also the time to file round the corners to make a smooth corner at the cuff opening. I like to keep the patina that the copper has picked up during it's life as a tube. No two pieces of tube will have an identical pattern on the inside. The older the tube, the more verdegris it will have on the inside.