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