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