Originally Posted by phizzle

Firstly, make sure your battery is not stuffed. Check the sulphuric acid level in each chamber, there should be 6 caps on the top you can undo to look inside. If low, top up with distilled (pure) water, not shit out of the hose. Go for a drive and charge the cells back up. If the battery is completely dry, get a new one, it's already rooted.

1) Make a pot of warm tea and find a toothbrush you won't need to use again
2) Take battery terminals off battery
3) Clean battery posts and terminals with warm tea. Use a toothbrush to get into all the nooks and crannies
4) Apply liberal amount of Vaseline to battery posts. This prevents them from corroding up again by disallowing contact with atmosphere yet still maintain electrical contact
5) Retighten everything back up
6) Don't forget to cup the balls