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