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