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