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