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