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