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