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