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