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