How to improve visualization skills (Graphing) Okay, so my problem is, that I have difficulty visualizing graphs of functions.
For example, if we have to calculate the area bounded by multiple curves, I face difficulty in visualizing that how the graph would look like. And in Integral Calculus, it is very important to plot the graph in some problems, so how can I improve my visualization skills? What can I implement in my daily math problem solving to improve these skills?
Edit:I am not talking about normal functions, simple ones like Signum function, absolute value function etc. I am talking about more complex ones like 
\begin{equation*}
y=e^{|x-1|+|x+2|}.
\end{equation*}

A friend of mine sent me a link to graph paper site: http://www.printablepaper.net/category/graph
gives you a choice of squares per inch and whether there are bolder lines each inch. Draw stuff. Do not imagine drawing things. Actually do so. If you want to solve $3 |x| = e^x,$ print out some graph paper, draw $y = 3|x|$ and $y=e^x$ on the same page and see what happens. 
There is a tradition in, let us call it, neuroscience, possibly a small minority opinion, that we have intelligence precisely because we have hands; one aspect of this is http://en.wikipedia.org/wiki/Homo_faber  I see lots of students on this site who have no ability to visualize in either two or three dimensions because they have never drawn any pictures or built any models of polyhedra. Part of this is that software such as mathcad took over early in many engineering and architectural fields; the people involved are the poorer for it. This has some references: http://www.waldorfresearchinstitute.org/pdf/Hand-Movements-Create-Intelligence.pdf
