Various insurance companies use similar and sometimes different metrics to arrive at a premium, things to consider and contribute to premium reduction are as follows:
1. Limiting mileage - be realistic but set as low as you can
2. Increase your excess - insurers like you to contribute more in the event of a claim, just balance to premium as upping excess by £500 for a £10 premium reduction is a false economy.
3. Park on a drive or better still in a garage if possible - helps premium reduction.
4. Make sure your occupation is listed correctly.
5. Adding named drivers who also drive the car helps however only do this if they have clean licenses and are actually going to drive it.
6. Consider an advanced driving course - again balance price vs premium reduction.
7. Consider removing add-ons such as breakdown cover, foreign travel - consider what’s actually appropriate for you.
These are the main things however they are pretty generic on comparison sites. Also look at companies not on comparison sites such as Aviva and Direct line too.
Finally once you found something reasonable, go to the insurers website directly as they may be cheaper..... cutting out the comparison sites’ commissions. If they are marginally more expensive then ring them as they may negotiate to secure your business.