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