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