My take on the Saiyan Transformation Tree! I tried to simplify it as much as possible and only included the most prominent forms that I still think are relevant to Dragon Ball. :
Dragon Ball: The 15 Best Transformations Ever
Strongest Dragon Ball Transformations
Dragon Ball: 10 Most Powerful Transformations (And 10 That Are Completely Worthless)
DB/Z/GT/Super: Goku's Transformations Quiz - By Moai
What dragonball transformation would you like to see more? - Quora
Dragon Ball Z Cell Transformations Painting — DBZ Store