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