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