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