README update for Mac 32-bit issue fogleman#7, and installing git+pip…

… on various platforms

README.md

@@ -11,14 +11,36 @@ http://www.youtube.com/watch?v=kC3lwK631X8
     cd Minecraft
     python main.py
 
-On Mac OS X, you may have an issue with running Pyglet in 64-bit mode. Try running Python in 32-bit mode first.
+### Mac
+
+On Mac OS X, you may have an issue with running Pyglet in 64-bit mode. Try running Python in 32-bit mode first:
 
     arch -i386 python main.py
 
-Or, try Pyglet 1.2 which supports 64-bit mode.
+If that doesn't work, set Python to run in 32-bit mode by default:
+
+    defaults write com.apple.versioner.python Prefer-32-Bit -bool yes 
+
+This assumes you are using the OS X default Python.  Works on Lion 10.7 with the default Python 2.7, and may work on other versions too.  Please raise an issue if not.
+
+Or try Pyglet 1.2 alpha, which supports 64-bit mode:  
 
     pip install https://pyglet.googlecode.com/files/pyglet-1.2alpha1.tar.gz 
 
+### If you don't have pip or git
+
+For pip:
+
+- Mac or Linux: install with `sudo easy_install pip` (Mac or Linux) - or find a package called something like 'python-pip' in Linux and install in your package manager.
+- Windows: [http://stackoverflow.com/a/12476379/992887](install Distribute then Pip) using the linked .MSI installers.
+
+For git:
+
+- Mac: install [Homebrew](http://mxcl.github.com/homebrew/) first, then `brew install git`.
+- Windows or Linux: see [Installing Git](http://git-scm.com/book/en/Getting-Started-Installing-Git) from the _Pro Git_ book.
+
+See the [https://github.com/fogleman/Minecraft/wiki](wiki) for this project to install Python, and other tips.
+
 ## How to Play
 
 ### Moving