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