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