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