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