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