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