Men's Sizing

• 1). Ask a friend to help you measure for the most accurate sizing.
  
  
• 2). Stand with your arms straight down at your sides.
  
  
• 3). Let your friend measure you around the largest area of your chest and arms.
  
  
• 4). Write the measurement down on a sheet of paper. Subtract 6 or 7 inches from that number to find your jacket size. For example, if your measurement is 49, your jacket size is a 42.
  
  
• 5). Determine the length of jacket you will need by using a size chart available at the clothing store or use one online if you are shopping for a particular brand. For instance, if you are 5 feet 11 1/2 inches to 6 feet 3 inches tall, you need a long length.
  
  

Women's Sizing

• 1). Determine your bust measurement. Using a cloth tape measure, bring the tape around the center or fullest portion of the bust.
  
  
• 2). Write down the bust measurement and take it with you to shop for a jacket.
  
  
• 3). Ask the salesperson for a size chart. Most brands vary slightly in their sizes. You can check online for a size chart if you have a particular brand in mind. Typically, a woman with a bust measurement of 37 inches would wear a size 14 jacket or a medium.