Cookie Clicker: How to get Golden Cookie Combos

Cookie Clicker Strategy Guide. No cheats or mods.
After a while playing Cookie Clicker, you may notice your progress grinds to a halt, even with frequent ascensions. This guide will show you how to get through the slogfest that is the Cookie Clicker late game.
Using this method it is also possible to get over one undecillion cookies and obtain all Heavenly Upgrades in under a week.