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