For more detailed instructions: DIY Pool Cooler
Step 1: Obtain or build some kind of "tower".
Learn more at: www.davidwilbur.com
Step 2: Cut up the fill material.
For more details: DIY Pool Cooler
Step 3: Next install the water sprayer system.
Additional info can be found here.
Step 4: Top it off and try it out.
Complete details: www.davidwilbur.com