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