You do it like this
Please note at the begining where it says url you need to put this symbol first [
I have to leave it off so you can see the code.
Also "Here" can be any message you want.
url=http://www."what ever you want" .co.uk]HERE[/url]
you can also add colour to "HERE" as below for example.
Please note,at the begining off the word color you need to add the symbol [ (left off so you can see the code)
url=http://www."what ever you want".co.uk]color=red]HERE[/color][/url]
Hope this helps.