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