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