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