There are lots of different ways to lanolise - I prefer using the Sudz n Dudz spray but I'm lazy

- lots of people swear by using lanolin soap or even a blob of lanolin nipple cream in with your wool wash when you're handwashing them (they take ages to dry doing it that way though apparently).
I lanolise mine (just a few good squirts!) every 2-3 washes - I can tell when they need it, they start feeling slightly damper and getting a little whiffier than normal.