How do you find your body volume using a tape measure?
ACCURATELY calculates a container into which your body will fit comfortably. Once you know the volume, fill the container with water.
Lower yourself into the water, permitting excess to spill over the top then climb out. By measuring the amount of water that has spilled over you are efficiently measuring your body volume. You can get a pretty accurate measurement by using the tape calculate to see how much the water volume has dropped after you get out of the water