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