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