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