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