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