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