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