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