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