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)(11,14)(12,16)(13,15)(17,21)(18,20)(19,22)(23,24)(25,26,31,28)(27,36,39,40)(29,34,30,35)(32,38,33,37)(2,5)(6,8)(9,11,13,17)(10,14,15,21)(12,18,19,23)(16,20,22,24)(25,27,30,38,31,39,29,37)(26,32,34,40,28,33,35,36)(1,3,4,7)(2,6,5,8)(10,15)(11,17)(16,22)(18,23)(25,27,29,37,31,39,30,38)(26,33,35,40,28,32,34,36)(9,12)(10,16)(11,18)(13,19)(14,20)(15,22)(17,23)(21,24)(25,28,31,26)(27,32,39,33)(29,34,30,35)(36,38,40,37)(12,19)(16,22)(18,23)(20,24)(25,29,31,30)(26,34,28,35)(27,37,39,38)(32,40,33,36)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.