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