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