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