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