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