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