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