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