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