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