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