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