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