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