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