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