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