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