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