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