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