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