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