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