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