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