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