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