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