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