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