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