note about installation

Author: ajnonaka

Docs/Amrvis.tex

@@ -37,6 +37,9 @@ \subsection{Overview}
 
 \subsection{Installing Amrvis}
 
+For 2D Amrvis, in the {\tt Amrvis} directory, simply type {\tt make}.
+For both 2D and 3D, make sure the {\bf AMReX} github repo is at the same level as {\tt Amrvis}.
+For 3D, you'll have to download VolPack and place it at the same level as {\tt Amrvis/}.
 VolPack is an external volume rendering package which is necessary for the 3D version of Amrvis.
 You can download VolPack using git by typing the following command.\\ \\
 {\tt git clone https://ccse.lbl.gov/pub/Downloads/volpack.git}\\ \\