Wearing a face covering in London is required on public transport but also advisable in places where social distancing is more difficult, for example in shops.
Face coverings must cover the mouth and nose and made of cloth or other textile through which you can breathe.
General guidance states that the material must be safe to use (some materials contain dangerous fibres), breathable, removed correctly (without touching your face), washed or disposed of correctly and social distancing measures should still be adhered to. Cloth face coverings should not be placed on young children under age 2, anyone who has trouble breathing, or is unconscious, incapacitated or otherwise unable to remove the mask without assistance. Please do your research first before using a home-made mask.