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