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