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