How to Build a Catapult

Well of course you can't start building a catapult without equipment involved. You must grab enough wood for your catapult and tools; such as screws, hammers, handsaws, rulers, springs, etc. (you get the idea).
You need to know how big you want your catapult and how much wood you might need. You also might want to see how much weight your catapult might carry, if it's too big, you might want to get some assistance. This is where you use a ruler and begin to measure it. You must need a flat base that at least touches the ground. The measurements must be exact so no mistakes will interfer when you're putting it together.
 

This is where it gets tricky. Putting the two boards that will hold the arm in place (forgot what they're called) wasn't so easy. What I mean is, when screwing them in, it kind of tilts them out instead of straighten them out. The reason why you want the board supporters for the arm straight is because you want your arm to be right in the middle and have a good angled launch.
When we screwed in the screws to the boards, it caused our boards to tilt out and not be even. But we made some adjustments so it's all good. To make the hole in each of the board, you have to make the exact measurements. You could use a metal bar to hold the arm in place. If the bar is top small or the hole in the arm is too big, you could use duck tape so the arm won't move from side to side. Once you've finally adjusted the arm in a good angling postion, you must know where you'll include the springs that will help you pull the arm back and launch. Also you must be aware of  the velocity on the arm, you'd want your golf ball to go far off with super speed.