The country of France is more than twice the size of the United Kingdom, but with a similar-sized population. This fact makes it a tempting prospect for drivers seeking a little solitude on the road. The main legal requirements that U.K. drivers from the need to be aware of before setting out with their cars to France are those pertaining to their car's headlights. Cars which are used to drive in countries which keep to the left-hand side of the road will invariably have headlights which are unsuitable for countries such as France, which drive on the right.
Right-hand drive cars have headlights which dip to the left so as to avoid blinding drivers approaching on the right. Unfortunately, this means that when driving on the right, they dip into the direction of approaching traffic and may dazzle drivers. For this reason, it is a legal requirement for right-hand drive cars to fit beam deflectors before driving in France.
It is a legal requirement when driving in France that headlights---and all lights be fully operational at all times. If stopped by the police because of a faulty bulb, drivers must be able to replace it with a spare or face a spot fine. For this reason, it's a good idea to always carry spares---although many modern cars require bulbs to be fitted by a garage.
French law used to require that all cars be fitted with yellow headlights as opposed to white ones. While this is no longer a legal requirement, foreign drivers wishing to blend in with the majority of French motorists can buy special yellow paint to apply to their headlights. Yellow bulbs may also be fitted.
The use of daytime headlights is compulsory in France if visibility is poor. Some industry bodies, such as the U.K.'s Automobile Association recommend their use at all times. Driving using sidelights is illegal in France.