If you don't have eclipse you can download it at http://www.eclipse.org/downloads/ 
Click to download
(It took me 1 hour to download on a 1.5 Mbit DSL connection)
From the Help menu select Install New Software
Give it the name python and enter the location
and click OK
Checkbox PyDev and click Next
Review and click Next
Accept the license and click Finish
Eclipse will download the python tools.
Checkbox the Certificate to trust it and click OK
You should get this message
Click Yes to restart Eclipse
From the Menu select Window -> Preferences
Select PyDev -> Interpreters -> Python Interpreter
If you don't have a python interpreter set up click New.
(this assumes you have python installed on your system somewhere)
Click Browse and find your python executable.
Mine happens to be at C:\Python27\python.exe
It will find these to add to the System path.
Click OK to close this window.
It will do a little set up
As a test click on File -> New -> Project
Select PyDev -> PyDev Project and click Next.
Give it a name and click Finish
A python project was created.
 Eclipse Download Page