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)(27,35)(28,32)(29,37)(30,33)(31,34)(36,39)(38,40)(1,2)(3,6)(4,5)(7,8)(9,11,15,12)(10,16,13,17)(14,19,22,20)(18,23,21,24)(25,27)(26,29)(28,33)(30,36)(31,37)(32,38)(34,35)(39,40)(2,5)(3,7)(9,11,15,12)(10,16,13,17)(14,20,22,19)(18,24,21,23)(25,28,31,39)(26,32,34,36)(27,33,37,40)(29,38,35,30)(3,7)(6,8)(9,12,15,11)(10,17,13,16)(14,20,22,19)(18,24,21,23)(25,29)(26,27)(28,38)(30,39)(31,35)(32,33)(34,37)(36,40)(1,3)(2,6)(4,7)(5,8)(9,13,15,10)(11,16,12,17)(14,21,22,18)(19,23,20,24)(25,30,31,38)(26,33,34,40)(27,36,37,32)(28,35,39,29)(1,2)(3,6)(4,5)(7,8)(9,14,15,22)(10,18,13,21)(11,19,12,20)(16,23,17,24)(25,26)(27,29)(28,36)(30,33)(31,34)(32,39)(35,37)(38,40)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.