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