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