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