1) Signal does not and can not protect information about who you are in contact with, when you contact or are contacted by them, and how long your conversation is.

2) Tor has been both infiltrated organizationally, academically broken, and is occupied by police on most of its exit nodes. This without the operational burden it puts on users. Tor is 'just okay' at protecting users, and should never be used alone.

3) Use a VPN you can trust. Most VPN (especially cheap and free services) are monitored by state police.

4) To add here, try not to have your pictures and locations uploaded online and do not carry a cell phone.

I want to add to the list:

5) Do NOT be a target. This is the opposite rule of the usual "if you have nothing to hide": DO NOT have anything to hide. Your opponents in the game of 'hide' are intelligence agencies and state police. It's much better that you comply and focus on narrow interesting technical problems than social or civil rights - as being outspoken and interested about the latter makes you a target.