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