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