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