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