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