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