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