I usually work on awareness first, helping them to connect with those muscles that were overly stretched or potentially damaged. Small, gentle movements to re-connect can be very healing. Work on unloaded activation of the TVA (transversus abdominus), pelvic tilts and contract-relax in the area. Progress as they feel comfortable. Some people think that over-contracting the abs can cause them to protrude more. The jury is out and I always go for awareness and communication with the client about what they are feeling.
Here is an anatomy blog about the TVA I wrote and a video about the pelvic floor muscles. I have a TVA video coming out soon, keep a watch or join my newsletter to receive it in 2015!