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