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