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