Context-free Grammar Exercise

Could someone explain me how to form a context-free grammar with all rules R by this example language, please? \begin{equation} L:=\left\{w c v c \overleftarrow{w} | w, v \in\{a, b\}^{+}\right\} \end{equation}

I already know that \begin{equation} \Sigma=\{a, b, c\} \end{equation} and V (non terminal symbols) maybe have to be \begin{equation} V=\{S, A, B, C\} \end{equation}

Thank you for helping.