How to implement a symbolic or concolic execution engine for a particular language?

I'm considering using concolic execution to test the programs written in a particular language such as C. I've read some papers introducing the basic concepts of symbolic and concolic execution. But I'm not clear about how to get it started.

So any one can give me some advice on the basics of the implementation of symbolic or concolic execution? what are the materials of the particular language should we know about to implement and design a concolic execution? I want to know how could I writing a symbolic or concolic engine for a particular language step by step. Thanks.