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