There are a few how to's on YouTube like this http://youtu.be/IlBby98Kg-w, I was going to do mine but realised it wasn't the gasket but over time oil had been spilt when filling up into the various wells and crevices under the plastic cover which ran down the engine block when it got hot.
Check for that first.
As for hughmungus I had spilt engine oil in the crevices beneath the oil cap. I found them when diagnosing a faulty cool pack. It was reassuring that the oil was golden and fresh, so unlikely to have pooled from a leak over time.
Get the plastic engine cover off, clean the area up and see if anything comes back. Hope it's a quick fix.
