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