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