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