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