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