Added more detailed instructions for how to use the repository.

Signed-off-by: Adam Vandenberg <flangy@gmail.com>

README

@@ -8,7 +8,7 @@ This repository contains UNOFFICIAL brews that have not been accepted into
 the master branch.
 
 These brews can be installed via the raw GitHub URLs, or by cloning this
-repository locally and installing off the local disk.
+repository locally and installing off the local disk. For more details see the "using" section below.
 
 This REPLACES the "Homebrew Duplicates" branch.
 
@@ -33,3 +33,27 @@ non-free
 
 other
     Other brews that have not been accepted into master.
+
+
+Using
+=====
+
+There are two ways to install packages from this repository.
+
+*Using Raw URLs*
+
+First you need to get your hands on the raw URL. For example, `https://github.com/adamv/homebrew-alt/raw/master/non-free/princexml.rb` is the raw url for the princexml formula.
+
+Then just pass that URL as a parameter to the `brew install` command, like so.
+
+`brew install https://github.com/adamv/homebrew-alt/raw/master/non-free/princexml.rb`
+
+*Cloning the Repository*
+
+Clone the repository to somewhere that you'll remember. This example creates a `LibraryAlt` directory under `/usr/local`.
+
+`git clone https://github.com/adamv/homebrew-alt.git /usr/local/LibraryAlt`
+
+Then to install a formula pass the full path to the formula into the `brew install` command. Here's another example that installs princexml.
+
+`brew install /usr/local/LibraryAlt/non-free/princexml.rb`