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