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