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