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