The correct answer is, don’t ever talk to law enforcement when your ass is on the line ever.
Simply refusing to answer is a good tactic.
One almost as good is say, Here, let me turn on my recorder, so that there is no question about what was said during this conversation.
The FBI refuses to conduct interviews that are recorded. So, they would likely leave you alone.
Another good tactic is to say - I do not recall, I do not remember, I do not know. The Clintons are famous for that one.
Or even when it is not. They may just find a way to make it so.