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