Geometric realizations of cluster categories of simply-laced types are studied in the following papers.
Philippe Caldero, Frédéric Chapoton, and Ralf. Schiffler, Quivers with relations arising from clusters ($A_n$ case).
Ralf Schiffler, A geometric model for cluster categories of type $D_n$.
Lisa Lamberti, Combinatorial model for the cluster categories of type $E$.
I didn't find papers which studied geometric realizations of cluster categories of non-simply-laced types. Have this problem been studied? Thank you very much.