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