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