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