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