Court says you must verbalize your fifth amendment rights to not have your silence used

http://www.scotusblog.com/

The scary part is two justices say the silence can be used by prosecutors regardless.....so if you are stopped, and brought in for questioning.....simply verbalize that I will not be answering any questions because of my fifth amendment rights.

This is very interesting.  The way I take it, what seems to  matter is whether you are actually under arrest?  In the case in question, the suspect had voluntarily gone to talk to the police. 
But I agree, I find this troubling and I'd like more examples of how the ruling could be used.

Now it's a condition or circumstance to remain silent. We should rename the bill of rights... how about the bill of permissions?