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