Creaking / knocking when I pedal

see? what i said. and what he said. job done.

have you taken out a BB before?

I did get pretty soaked a few weeks ago, so maybe I did get some water in there. I've never taken a BB out, I assume I'll need a specific tool? It is something I'd quite like to give a try though. Only downside is I'm not graced with a great selection of tools or knowhow.