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