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