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)(11,15)(12,17)(13,18)(14,19)(16,20)(21,23)(22,24)(25,26,30,29)(27,32,35,31)(28,36,37,33)(34,38,40,39)(2,3)(6,7)(9,11)(10,15)(12,21)(13,22)(14,20)(16,19)(17,23)(18,24)(25,27,30,35)(26,31,29,32)(28,34,37,40)(33,38,36,39)(1,3,5,2)(4,7,8,6)(11,20)(15,16)(21,24)(22,23)(25,27,30,35)(26,31,29,32)(28,34,37,40)(33,38,36,39)(1,4,5,8)(2,6,3,7)(9,11)(10,16)(12,21)(13,23)(14,20)(15,19)(17,22)(18,24)(25,27)(26,32)(28,34)(29,31)(30,35)(33,39)(36,38)(37,40)(9,12)(10,17)(11,21)(13,19)(14,18)(15,23)(16,22)(20,24)(25,28,30,37)(26,33,29,36)(27,34,35,40)(31,38,32,39)(9,13,14,17)(10,18,19,12)(11,22,20,23)(15,24,16,21)(25,29,30,26)(27,32,35,31)(28,33,37,36)(34,38,40,39)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.