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