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