Clothing. You should avoid clothes that may get tangled in the chain, or in a wheel or may obscure your lights when you are cycling.
Light-coloured or fluorescent clothing can help other road users to see you in daylight and poor light, while reflective clothing and/or accessories (belt, arm or ankle bands) can increase your visibility in the dark.
You should wear a cycle helmet that conforms to current regulations, is the correct size and securely fastened. Evidence suggests that a correctly fitted helmet will reduce your risk of sustaining a head injury in certain circumstances.