Record details of your bike. Frame number (normally found underneath the bike between the pedals or where the back wheel slots in), security marking number, other distinguishing features, and take a photo.     

Use Sold Secure Gold standard locks as a minimum. Locks tested to Powered Cycle Diamond within the Sold Secure range even have resistance to small angle grinders. Use two different types of locks, with at least one being a high quality D-lock. It takes thieves a few seconds to cut through poor quality locks - make it as difficult for them as possible - two different locks may require two different tools to break.

Make the locks and bike hard to manoeuvre. Secure your bike as close to the stand as possible. Try not to leave any slack chain or lock on the ground, this allows thieves to smash the lock with a hammer against the ground.

Take parts that are easy to remove with you. For example, saddles and wheels. Or use locking skewers, which can increase security by securing the bike's components to the frame permanently, making it difficult for thieves to steal parts such as saddle or wheels.

Lock your bike at recognised secure cycle parking. It should be well lit and covered by CCTV, overlooked by buildings and with plenty of members of public, passing by. If possible, lock both wheels and the frame.

Take the same care to lock your bike securely at home. Bikes get stolen from inside the home, communal hallways, gardens, sheds and outside your property. 

If your bike has been stolen, contact the police. Give them your frame number, any security marking number, photo and any other details. You can also register your bike with its frame number retrospectively as stolen on an approved bike registration database. (https://www.bikeregister.com/)

Never leave your bike unlocked & unattended. A 2 minute pop into the shop is more than enough time for someone to take that opportunity to steal your bike. ALWAYS lock it safely.