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)(11,18,12,16)(13,22,23,19)(14,20,24,21)(28,36)(31,38)(34,40)(37,39)(1,3,5,8)(2,6,4,7)(9,11,15,12)(10,16,17,18)(13,20,23,21)(14,19,24,22)(25,26)(27,32)(28,31)(29,33)(30,35)(34,39)(36,38)(37,40)(1,2,5,4)(3,6,8,7)(10,17)(11,12)(19,22)(20,21)(25,27)(26,30)(28,34)(29,35)(31,37)(32,33)(36,40)(38,39)(1,2,5,4)(3,6,8,7)(9,12,15,11)(10,18,17,16)(13,21,23,20)(14,22,24,19)(25,28,29,36)(26,31,33,38)(27,34,35,40)(30,37,32,39)(1,2,5,4)(3,6,8,7)(9,13,15,23)(10,19,17,22)(11,20,12,21)(14,16,24,18)(25,27)(26,32)(28,34)(29,35)(30,33)(31,39)(36,40)(37,38)(1,4,5,2)(3,7,8,6)(9,14)(10,20)(11,19)(12,22)(13,18)(15,24)(16,23)(17,21)(25,26)(27,30)(28,31)(29,33)(32,35)(34,37)(36,38)(39,40)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.