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