Welcome to TFP! For your question, you'll want to review either of the links below depending on your pool type. They also address the chemical aspect. But basically after standard chemical balancing and final cleaning, increase the FC to "SLAM" level (see our FC/CYA Chart), let it fall a bit before adding algaecide (if used). Close when the water temp is below 60. Don't forget to review our ABCs of Pool Water Chemistry for more info, and let us know if you have any questions along the way.