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