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