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