You can mark the curve with a node with diamond shape and customize its aspect ratio for your needs.

\documentclass{article}
\usepackage{tikz}
\usetikzlibrary{decorations.markings,shapes}
\begin{document}
 \begin{tikzpicture}[decoration={             
                    markings,
                    mark connection node=connode,
                    mark=at position 0.5 with {
                    \node[transform shape,shape=diamond,fill=white,draw] (connode) {};
                        }
}
  ]
  \node (0)                     {};
  \node (1) [right       of=0]  {};
  \node (2) [below right of=1]  {};
  \path (0) edge[out=0, in=135, postaction={decorate}] (2);
 \end{tikzpicture}
\end{document}




I have edited the code for a slightly better placement however it is still not perfectly following the curvature, this is due to the size of the diamond shape compared to the curvature in the markings library and I don't see a direct fix other than drawing to an intermediate diamond node and then drawing to the final point. 

TikZ: How to decorate a path with the open diamond arrow tip that "bends" with the path?
I want remove Shipping Information, Shipping method, and Payment method for now i don't need to add all of this, i only want customer can view product detail and go for checkout.

i tried to remove it at time of checkout it giving me error message that process can not go further for checkout.
