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