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