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