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