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