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