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