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