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