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