[serf]

Go to places where it's unavoidable. Courthouses, high security events, political rallies. Any place where the consensus is that they "need to keep the peace".

Live in a place that is considered high crime by the surrounding communities. Be a different color/religion/orientation/gender than the police officer nearest you. Be financially distraught.

Be poor, and have no where to live.

Live flashy within the law. Drive a fast looking car. Paint it red. Put some loud (but entirely legal) exhaust system on it. Lower it to the limits of legality, and put some big chrome wheels on it.

Be empathetic and understanding towards criminals and the reasons they became labeled as such. That's the best way to meet a police officer, probably.

I've never said something this honest to another individual on hacker news before : I envy you who can avoid the police. I'm not familiar with London, but it's miraculous here in the states.