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