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