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