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