One vertex per element, one color per generator, with an edge from x to x·s.
(2,4)(3,7)(9,10,13,12)(11,14,15,16)(19,23)(21,24)(25,26,30,31)(27,33,34,28)(29,37,38,32)(35,36,39,40)(2,4)(6,8)(11,15)(14,16)(17,18,20,22)(19,21,23,24)(26,31)(27,34)(29,38)(36,40)(1,2,5,4)(3,8,7,6)(9,11,13,15)(10,14,12,16)(25,27,30,34)(26,28,31,33)(29,39,38,35)(32,40,37,36)(1,3,5,7)(2,6,4,8)(17,19)(18,21)(20,23)(22,24)(25,28)(26,27)(29,40)(30,33)(31,34)(32,39)(35,37)(36,38)(1,4,5,2)(3,8,7,6)(9,12,13,10)(11,16,15,14)(25,29,30,38)(26,32,31,37)(27,35,34,39)(28,36,33,40)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.