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