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