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