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