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