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