One vertex per element, one color per generator, with an edge from x to x·s.
(2,4)(6,10)(7,12)(15,21)(16,23)(18,25)(19,24) involution — undirected(1,2)(3,4)(5,6,9,10)(7,11,12,8)(13,14)(15,18)(16,19)(17,20)(21,25)(22,26)(23,24)(27,28)(5,7)(6,11)(8,10)(9,12)(13,14,17,20)(15,18,21,25)(16,19,23,24)(22,26,27,28)(13,15)(14,18)(16,22)(17,21)(19,26)(20,25)(23,27)(24,28) involution — undirected(5,8)(6,7)(9,11)(10,12)(13,14)(15,18)(16,24)(17,20)(19,23)(21,25)(22,28)(26,27) involution — undirected(5,7)(6,11)(8,10)(9,12)(13,16)(14,19)(15,22)(17,23)(18,26)(20,24)(21,27)(25,28) involution — undirectedA 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.