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