phpBB hide Administration Control Panel Link

I have a forum in phpBB, want to hide the link to ACP from normal users.
Any ideas on how to do it???

It already works like that — the phpBB ACP link is only visible if you’re logged in as a user with admin access.

Unless the theme you’re using explicitly puts a link there without using appropriate tagging.
Test permissions as a Guest and Member to see if the link does hide.