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