Here in the Ozarks severe storms often bring hail. It's important to know how measure and accurately take a picture of it.
When it comes to measuring hail it's not a good idea to use your hand as a comparison. For instance my hand is significantly smaller than Daniel's hand. Via picture we can't really tell what size that is.
To measure hail you want to compare it to objects like pocket change up to a softball. Items like a ping pong, golf ball, tennis ball, a teacup, and a softball. You want to take the diameter of that with a ruler or measuring tape and measure across.
For instance, a softball is almost 4 inches, a teacup which is something you probably have at home it's 3 inches, a nickel is three quarters of an inch.
Line up the hailstone with the object that it matches to and put the ruler right in front of it. Then when you go to take a picture of it make sure your camera is centered horizontally.