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