A female checking template would be good
A series of straight cuts on the table saw would work for the internal cove, then remove the waste with a chisel.
The other side could be done on a bandsaw or table saw. Then hand planed or sanded to the proper curve. The templates can be used "as you go" to get a consistent profile.
The answer to your question will only be as detailed and specific as the question is detailed and specific. Good questions also include a sketch or a photo that illustrates your issue. (:< D)