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