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