From My Site: Ectomatter.com

I have noticed a large number of people on this forum do not know how to take their body fat measurements. So here is a quick walkthrough. Mods move this to the correct section if it is not there now, I was not sure where to put it.

THE CALIPER
For starters, you need to get yourself a body fat caliper. You can drop 50-100 bucks and buy a digital caliper, or you can go with a cheap little accumeasure caliper (like me )


These can be purchased at many fitness stores/depots or ordered online for very cheap.

THE MEASUREMENT
There are many different techniques for this, but in my experience, the most accurate technique is the 9-site Parillo. (works for men and women).

It is not easy to do on your own, so you are better off to ask someone for help. However, with a little practice and creativity, some people are able to take their measurements on their own.

Here are the 9 places on your body where you take the measurements:

• Pectoral/ Upper Chest
  A diagonal fold, halfway between the nipple and the front of the underarm crease.
  
• Tricep
  A vertical fold halfway between the shoulder and elbow joint, directly over the tricep.
  
• Bicep
  A vertical fold halfway between the shoulder and elbow joint.
  
• Suprailiac
  A diagonal fold following the natural angle of the hipbone.
  
• Lower Back/Kidney
  A horizontal fold about 2 inches to the right of the spine, directly over the kidneys.
  
• Subscapular
  A slightly angled vertical fold between the right shoulder blade and the spine.
  
• Umbilicus/Abdomen
  A horizontal fold one inch to the right of the navel.
  
• Calf
  A vertical fold directly in the middle of the calf muscle.
  
• Upper Thigh

Now, Pinch an inch. For most measurements, using your thumb and index finger, you squeeze approximately 1 inch of fat and then use the caliper to measure the amount of millimeters that the fat takes up.
*If you are using a plastic caliper, remember to use the slider piece which points to the number of millimeters.*

THE MATH
Nope, getting a "20" pinch on your abdomen does not mean you have 20% BF.

1. Add up the 9 measuremenst that you took with the caliper
2. Divide the total sum of the skinfold measurements by your weight
3. Multiply the result by 27.

While I am at it, to find your total fat in pounds: Mulitply your weight by your BF % and divide by 100. To find your pounds of muscle (LBM) just subtract your pounds of fat from your total weight.

Things to Note:

• Take these measurements in the morning after you go to the bathroom and before you eat. If you take the measurements later on in the day you will very likely have your numbers thrown askew by water/food weight.
• If you are having trouble taking the measurements yourself, try using clothes pegs to act as your fingers. People generally have problems taking measurements on the triceps, biceps and upper back. You should be able to reach over your shoulders to take the upper back (takes practice), but for the bicep and tricep, give the clothes pegs a shot.
• Where to pinch: I suppose it varies from person to person, but generally i place my fingers an inch apart , then pressdown and squeeze. The resulting 'fold' is what i measure. Once you have done it a few times you will develop a system that works for you. While it may not be 100% accurate, it is very precise when it comes to consistency.
  
  When you are pinching you should be feeling fat. Some parts of the body (ie biceps and upper back) yield lower numbers and it will feel different when compared to a pinch of your abdomen. I shouldn't hurt when you do this.

If you all can think of anything to add to this HOW TO, just post it and I can made additions.

Cheers.