Sleeve HemsTo add some weight and stability to the sleeve hems of my
Sparkly Tweedy Jacket, I used a bias cut strip of interfacing along the hemline. After sewing one side of the upper sleeve to the lower sleeve, I pressed the hem up by its hem allowance to mark the hem line. Because I chose to use a sew-in interfacing (hair canvas), I hand-stitched the interfacing to the fabric using catchstitches and a basting stitch. The key here is to make sure the interfacing extends down into the hem allowance (for a sew-in, it should extend down by 1/2 inch), so when the hem folded up and sewn, the interfacing adds extra stability to the hem.
For this jacket, I chose to make a slit rather than the standard vented sleeve, so I mitered both corners of the slit. After mitering the corners, I hand-stitched the hems using catchstitches and sewed the remaining sleeve seams.
Easing the Sleeve CapOne of the most difficult things for me to do is ease the sleeve cap and sew it into the armhole. For jackets, I learned an amazing technique that really makes it easier than the usual "baste a couple rows along the cap and gather the fullness" procedure.
1. Cut two bias strips of wool that are 2 inches wide and the length of the area that needs to be eased (usually marked by dots on the sleeve patterns). Mark the center of each strip with a clip.
2. Match the center of the strip with the top of the sleeve cap and pin to the inside of the sleeve, matching the raw edges.
3. Beginning at the top of the sleeve cap, anchor the needle and begin sewing, just inside the seam allowance, down the cap toward one of the dots, making sure to stretch the bias strip as much as possible as you sew. It is important to stretch the bias strip, as this automatically eases the sleeve cap. Repeat on the other side and on the other sleeve.
4. Check the shape of the cap, which should be slightly cupped. Check the fit with the armhole to make sure enough of the sleeve has been eased.
5. With this process, the bias strip acts as the sleeve head, which is traditionally an extra piece of wool or mohair that is sewn into the sleeve cap for extra shaping for the cap.

After easing the sleeve cap, I further shape it with a steam iron and a tailor's ham. After that, I just pin the sleeves into the corresponding armholes and sew.
Shoulder PadsI still remember the '80s and those big, bold shoulders, so I'm generally not a huge fan of shoulder pads. However, I learned that they are an important element for tailored jackets, as they shape and smooth the jacket shoulders, lending a certain polish to the finished product. Commercially available shoulder pads seem to be on the thick side, so I make my own now. There are patterns out there, but check out the shape in the photo below and size it for the jacket you are making. Some notes:
1. I use a Pellon fleece that is used for craft projects --- I found mine among all of the interfacings at Joann's.
2. Each of my shoulder pads has 3 layers of fleece cut in three different sizes. You can add more layers if you want a thicker pad.
3. Tailor baste the 3 layers together, shaping the pad into a curve as you stitch. If you want, you can cover the pads with muslin or a coordinating fabric for a more finished look, which is important for unlined jackets.