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