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