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