Items needed are:
*1 Straw that is large enough to see down the hole
*1 foot piece of string
*A weight that is heavy enough to keep your string stiff
*Scissors & Tape
Step 1: Getting Started
To get started you need to cut your string about a foot long or shorter depending on what feels more comfortable for you. Put the string through the hole of the protractor and attach it with a piece of tape.
Step 2: Attaching the Weight
Next your going to attach a small weight. I used a big paper clip as my weight. Other things you can use is a washer or anything that is heavy enough to keep your string stiff when it is dangling.
Step 3: Your Done!
With your straw that should be large enough to see through the hole, align it to where the 90 degree mark is on your protractor. Then attach it to the protractor with tape. Try making it as straight as possible.