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