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