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