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