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