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