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