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