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