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