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