Most importantly is adjusting client expectations at the front end of the representation. The criminal client should be informed how the process of delay works in their favor. How police witnesses lose memory, how prosecutors lose interest, how mitigating facts can be developed over time to favor the client.
Adjusting client expectations, notwithstanding, is never a justification for tardiness in other areas of the representation. For instance, returning phone calls and keeping clients informed of case developments. This is where fast service is king and where improved client loyalty is developed.
In other words, take good care of your clients by responding quickly to their questions. But let them know, up front, the best results in a criminal case often come after long periods of delay.