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