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