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