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