Travel by land. Land is possible only by train through the Chunnel. There are several locations to board trains that travel through the Chunnel, including London and Paris. Check the map at raileurope.com.
Book a flight. Several airlines fly between French and English destinations. Flying often takes longer than other ways of traveling, because you have to go get to the airport well before your flight and stand in line to go through security. LowCostAirlines.org has a complete list of airlines that fly between the two countries.
Go by sea. Ferries carry passengers and cars, and are a great way to enjoy the scenery.