How can I reduce my extremely broad shoulders? (Photo)

broad shoulders cannoot be fixed although some people are doing surgery to reduce the clavicle length I think this is risky and has a lot of scarring. you can do liposuciton on yoru arms and shoulders and waist to give you the Illusion of being smaller.  Best, Dr. Emer.

A consultation with a board certified plastic surgeon is encouraged. This may be corrected using high defintion VASER liposuction.  The Gold Standard for superior liposuction results requires use of the advanced technology of ultrasound assisted VASER liposuction. As an official trainer of VASER liposuction, I perform full body liposuction cases every week. VASER liposuction has been the only modality that has consistently resulted in outstanding liposuction outcomes. VASER liposuction ensures a smooth contour regardless of degree of excess fat by virtue of being able to remove any and all remaining fat comprehensively and uniformly. If skin redundancy is observed, Renuvion technology can be simultaneously applied to tighten your skin to optimize your overall contour outcome. A Skype or FaceTime consultation with a VASER specialist will help you get an accurate recommendation and pricing.
Respectfully, 
Arian Mowlavi MD, FACS
Realself 100 Hall of Fame Inductee

Your best option is most likely arm Liposuction that is done circumferentially and  including the shoulder or around the deltoid muscle. 
The amount of change is directly proportionate to the thickness of your fat layers in these areas.
Liposuction when done correctly delivers spectacular results with consistent high patient satisfaction.arms are anatomically highly favorable for top-notch  results especially compared to lower extremities.
Arms  can be technically challenging and choosing an experienced provider is the number one assurance that things don’t go array.
I suggest having multiple in person consultations with providers in your area. Look for providers who can demonstrate numerous before and after pictures.
Read all the negative reviews as well as confirming positive reviews on various review websites like real self, yelp, health grades, rateMD, vitals etc.
Positive reviews are reassuring and a good sign but I find the negative reviews tells the real picture post accurately. 
Unmanipulated organic reviews tend to fall with a fairly even distribution among each of these review websites. Businesses with skewed distribution with excessive number of reviews on one or two websites show evidence of manipulation.
Arm liposuction can be done as an awake office-based procedure using local anesthesia with or without sedation.  Patients see around 80% of results at six weeks.
My practice is devoted exclusively to Liposuction and fat  transfer procedures. We do all of these without general anesthesia as office based procedures. With experience results become predictable and consistent.
I recommend investing in significant time and effort and having in person consultations with multiple providers before making a decision to permanently change your body.
Best, 
Mats Hagstrom MD