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