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