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