Good Resources
http://www.raywenderlich.com/12139/
The Podfile
An example podfile with the ios target platform and one library version number specified and another library version not specified:
platform :ios, '5.1'
pod 'BlocksKit', '~> 1.8.3'
pod 'Reachability'
Updating The Pods Controlled Libraries
Run Applications > Utilities > Terminal
Navigate to your projects directory. E.g. right click a file in your project and select Get Info, then copy the path and use
cd /User/MYname/........
Then type
pod install
An example install process
Adams-Mac:Pererro Adam$ pod install
Analyzing dependencies
Downloading dependencies
Installing BlocksKit (1.8.3)
Installing Reachability (3.0.0)
Using libffi (3.0.13)
Generating Pods project
Integrating client project
Adams-Mac:Pererro Adam$