You’ve found the perfect blazer. It’s the exact color and style you’ve been wanting for ages; but unfortunately, it doesn’t fit. The sleeves are a bit too long (or short), the length is somewhat too long (or short), the waist needs some nipping in (or letting out), the shoulders could use some padding, and the buttons need replacing. Your perfect blazer could end up as a perfect nightmare, unless you’re able to do some tailoring. If you can't afford the money to go to a professional, altering a blazer at home doesn’t have to be major surgery.
Try on the blazer. Mark with pins where it needs alterations. Pin on the inside of the jacket until it fits perfectly. Try it on several times until all the pins are in place. Compare the blazer to one that fits perfectly in your closet to be sure of sizing.
Turn the jacket inside out. Begin with the sleeves. If the sleeves are too long, these should now be pinned up to the correct length with at least one pin. If too short, you have to work with the excess material that's in the hem.
Use the seam ripper to take out the old hem and release the lining. Try on the jacket again to be certain of the length. If you are lengthening the sleeves, iron out the material on the inside, so the old hemline won't be creased before you begin pinning.
Use the ruler to go around the cuff and make a new hem that's straight. Pin the cuff all the way around as you insert the lining inside the new hem, smoothing it out as you go. Repeat for the other sleeve, making sure the length matches.
Try on the jacket carefully with all the pins in place. Make any adjustments on the new hems and sew by hand. Iron the new hem on the inside of the jacket and turn right side out.
Try on the blazer. Mark with a pin where you want the new length. Pin on the inside of the jacket until it's the correct length all the way around.
Use the seam ripper to take out the old hem and release the lining. Try on the jacket again to be certain of the length. If you're lengthening the blazer instead of shortening it, iron out the creased material on the inside before you begin pinning.
Use the ruler to go around the new hem to make it straight straight. Fold the jacket in half to ensure the hem is even. Pin all the way around as you insert the lining inside the new hem, smoothing it as you go.
Try on the blazer when all the pins are in place. Make any adjustments on the new hem and sew it by hand. Iron the hem on the inside of the jacket and turn it right side out.
Altering the Waist
Make darts or delete darts in the blazer until if fits perfectly. Most blazers fall straight, but closely cropped business blazers can be more tailored and come with darts to nip in the waist.
Delete darts by using the seam ripper to carefully open up the material. Repeat on the opposite side of the jacket. Darts can be added or deleted at the front, back or near the sides of the jacket to provide a custom fit. Iron down the areas if needed on the inside of the jacket.
Add darts by opening up the lining to be able to reach the inside of the blazer material. Open the lining at the front seams (where the buttons and button holes are placed). Try on the jacket and mark with pins on the outside of the jacket where it's too big and boxy. Take in the material evenly on the front of the blazer, as well as the back side and near the side seams, if necessary.
Move the pins from the outside to the inside of the jacket. You already opened up the lining, so slide the pins into place where the pins on the outside hit the inside. Make enough darts so the jacket fits perfectly. Sew the darts by hand if your sewing machine won't fit inside the lining. Remove the pins as you go.
Sew back up the seams. The easiest way to make a jacket smaller is to move over the buttons, but this doesn’t provide the custom fit of darts.
Adding Padded Shoulders and Buttons
Purchase or use a set of padded shoulders from an old jacket. If your blazer doesn't look full enough in the shoulders, place the new pads into the blazer and pin in place.
Try on the blazer to make sure both pads are lined up exactly. Hand sew into place.
Choose new buttons or move over the old buttons to make your blazer fit tighter. Blazer buttons are usually repeated in a smaller size for the cuffs. Visit a notions store and pick up two button sizes in a matching style. Sew on the buttons by hand in the same manner the original buttons were attached.
Taking in the waist by adding darts is the hardest alteration. If you don't feel comfortable doing it, seek a professional.