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