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