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