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