This is a fantastic resource. It covers gravity water supply fundamentals, walks the reader through a branched system set of hand calculations, and sheds light on design details/drawings.
I’d recommend going through pages 9-62 (blank design forms in the appendix), and using the hand calculation process results to compare results from EPANET analyses of the same system presented in this manual. This manual truly compliments the Jordan manual. It is another oldie, but goodie.