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