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