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