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