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)(11,17,19,14)(12,20,21,15)(18,22,24,23)(25,26)(27,36)(28,32)(29,34)(30,33)(31,35)(37,39)(38,40)(9,11)(10,14)(12,18)(13,19)(15,22)(16,17)(20,23)(21,24)(25,27,30,34)(26,29,33,36)(28,39,38,31)(32,35,40,37)(2,5)(6,8)(25,28,31,27,30,38,39,34)(26,32,35,36,33,40,37,29)(9,12,13,21)(10,15,16,20)(11,18,19,24)(14,22,17,23)(26,33)(29,36)(32,40)(35,37)(1,3,4,7)(2,6,5,8)(11,19)(14,17)(18,24)(22,23)(25,29,31,32,30,36,39,40)(26,34,35,28,33,27,37,38)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.