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