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