I have insurance with a tracker. It costs about 10 Euro per month. If the bike is stolen, they first try to find it with the tracker. Bikes with trackers are usually put temporarily in public space close to where it's stolen during a cool-off period to check if the tracker is still operational/followed. Usually the insurance will just recover the bike from this cool-off spot. If the insurance company cannot find the bike through the tracker, they'll buy you a new bike.

Besides that, the rule is to always make your bike the least attractive to steal. Use two locks eg. a ring lock through the rear wheel and a chain lock through the front wheel, frame, and attached to something stationary (so they can't through the bike in a van and break the locks later). In general it's also good to put it in places where someone would notice if anyone tries to steal the bike, but not so busy that no one would notice and feels responsibility. Bonus points (remember the 'least attractive' rule), put it in some place where there are bikes that are much easier to steal (eg. not attached to a fixed object).

But expensive and heavy locks suck and the ever present thought in your head planning a good parking spot etc. kills the joy of it.

It's also a cultural/facilities thing. Eg. in The Netherlands many cities have bike parking with supervision and nobody minds if you attach your bike to eg. a lamp post. And most cities have plenty of lamp posts, so no real planning necessary :).