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