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