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)(11,14)(12,15)(13,16)(17,21)(18,22)(19,23)(20,24)(25,26,30,34)(27,31,36,40)(28,33,29,32)(35,38,37,39)(1,2)(3,6)(4,5)(7,8)(9,11,13,17)(10,14,16,21)(12,19,20,18)(15,23,24,22)(25,27,30,36)(26,31,34,40)(28,37,29,35)(32,38,33,39)(11,17)(14,21)(18,19)(22,23)(26,32)(28,29)(31,38)(33,34)(35,37)(39,40) involution — undirected(2,5)(6,7)(9,12,13,20)(10,15,16,24)(11,18,17,19)(14,22,21,23)(25,27)(26,31)(28,37)(29,35)(30,36)(32,38)(33,39)(34,40)(1,3,4,8)(2,6,5,7)(10,16)(14,21)(15,24)(22,23)(25,28,30,29)(26,33,34,32)(27,35,36,37)(31,38,40,39)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.