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