Update README.md

osx instructions

README.md

@@ -20,6 +20,16 @@ Scripts for building the web and pdf versions of the book are in `scripts/` dire
 - When building the web book, the website is stored in the `output/webBook` directory.  Opening up `output/webBook/toc.html` will open up the table of contents.
 - When building the pdf book, the pdf is created at `output/ofBook.pdf`. `output/ofBook.tex` is also created, for debugging purposes.
 
+## OSX
+1. install pip at the terminal ```sudo easy_install pip```
+2. install [beauitful soup 4](http://www.crummy.com/software/BeautifulSoup/) (bs4)
+  - Method 1: 
+    1. Get the python package manager, [pip](https://pip.pypa.io/en/latest/installing.html).  This involves downloading `get-pip.py` and running it from command line.
+    2. Run `pip install beautifulsoup4` from the command line to install BeautifulSoup
+  - Alternate [installation methods](http://www.crummy.com/software/BeautifulSoup/bs4/doc/#installing-beautiful-soup) for bs4
+3. Install [pandoc](https://github.com/jgm/pandoc/releases)
+4. Install [basictex](http://www.tug.org/mactex/morepackages.html)
+
 ## Windows Installation of Dependencies
 1. Download and install [Python 2.7+](https://www.python.org/)
 2. Download and install [beauitful soup 4](http://www.crummy.com/software/BeautifulSoup/) (bs4)