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