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)(25,26,31,36)(27,37,39,32)(28,35,30,33)(29,34,38,40)(3,7)(6,8)(10,15)(13,16)(17,20)(21,23)(25,26)(27,37)(28,33)(29,40)(30,35)(31,36)(32,39)(34,38) involution — undirected(1,2,5,4)(3,6,7,8)(10,15)(11,18)(17,20)(19,24)(25,27,31,39)(26,32,36,37)(28,38,30,29)(33,40,35,34)(9,11,14,18)(10,16,15,13)(12,19,22,24)(17,23,20,21)(25,28,31,30)(26,33,36,35)(27,38,39,29)(32,40,37,34)(1,3)(2,6)(4,8)(5,7)(9,12,14,22)(10,17,15,20)(11,19,18,24)(13,21,16,23)(25,29)(26,34)(27,28)(30,39)(31,38)(32,33)(35,37)(36,40)(1,4,5,2)(3,8,7,6)(9,13,14,16)(10,18,15,11)(12,21,22,23)(17,24,20,19)(25,30,31,28)(26,35,36,33)(27,29,39,38)(32,34,37,40)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.