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