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