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