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