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