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