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