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