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