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