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