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