One vertex per element, one color per generator, with an edge from x to x·s.
(1,2)(3,5)(4,7)(6,8)(9,10,14,19,15,18,13,26)(11,20,23,16,22,31,27,30)(12,17,24,34,25,32,28,33)(21,36,39,40,37,35,38,29)(9,11,14,23,15,22,13,27)(10,16,19,31,18,30,26,20)(12,21,24,39,25,37,28,38)(17,29,34,36,32,40,33,35)(2,5)(3,8)(6,7)(9,12)(10,17)(11,21)(13,28)(14,24)(15,25)(16,29)(18,32)(19,34)(20,35)(22,37)(23,39)(26,33)(27,38)(30,40)(31,36) involution — undirected(10,18)(11,22)(17,32)(19,26)(21,37)(23,27)(33,34)(38,39) involution — undirectedA 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.