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