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