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