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