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