Introduction: Tailor Your Jacket Sleeves

About: I'm a designer and engineer, but more importantly I just love to fix, build, make and break stuff.
Custom-tailor your jacket for a slender, fitted look.

The example here is a great jacket, but the sleeves were too full. Slenderizing them gives the jacket a whole new look!

This is basic sewing stuff, and I am a basic sewer. You can do it yourself, it's easy!

You will need:
Scissors (fabric scissors are best)
Sewing Machine (you CAN do it all by hand, but it will obviously take longer)
Seam Ripper
Fabric Crayon, or other marking tool

Step 1: Determine the Correct Fit

First of all, inspect your sleeves and determine if the alteration is feasible. In my example, the alteration was very easy. The cuff-button thing didn't get in the way, because my seam line went straight across it. Because I am not shortening this sleeve -- just tightening the diameter -- I don't have to move this cuff-button thing. It can be moved easily though.

Put on your jacket and pinch one of the sleeves at the seam (starting from your armpit to your wrist). You will use pins to mark where you will be sewing. Be sure to not pinch around the arms too tight, or you will have trouble bending your elbow. The most critical part seems to be on the forearm a few inches down from your elbow... determine the maximum amount of fabric you will be taking in at this point.
You should do this with only one sleeve for now. You can do the other one later.

Step 2: Detach the Sleeve Lining

Take off your jacket, leaving the pins in the measured sleeve. Turn the opposite sleeve inside-out.
If your sleeve doesn't have a lining, skip this step.
If it does, cut the threads that bind the lining to the jacket sleeve. In this example, this step was easy; the lining was easily detached from the top hem.
Peel back the lining to expose the jacket's original seam.

Step 3: Mark Your Seam

Using the measured sleeve as a guide, lie it underneath your inside-out sleeve and transfer the measurements to this sleeve with a fabric crayon.
Where the original seam meets the armpit, taper your marking towards this seam in order to blend the new one with the old.

Step 4: Sew!

Again, a sewing machine s obviously optimal for this. I won't explain how to use one here... but if you don't know how, don't be afraid. It's actually very easy!
Sew from the end of the wrist to the armpit along your marked line.

Step 5: Test, Copy, Sew Again

Put on the jacket (take caution if you still have pins in the other sleeve) and test-fit it. If it works, great!
If not, you'll need to rip out the stitch and adjust your measurements .
Transfer your correct measurements to the other sleeve and sew it also (after, of course, you open up the sleeve lining if it is present).

Step 6: Finish

Cut off the excess fabric.
Now you can finish by re-attaching the jacket to the lining. If you tightened up the circumference of the sleeve a lot, you may not be able to fit it on your sewing machine, like in my case. So I had to hand-sew.

Enjoy the new look!