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