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