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