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