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