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