How did Britian and France try to prevent war with Germany?Please answer as soon as possible

Agreed with the above post.  They buried their heads in
the sand and hoped Hitler would go away, mostly.  Then they ignored him furhter when he
did not, and at their own peril.  However, France did build a large military and an
expensive, massive fortification called the Maginot Line that they believed would be
impossible to breach.  Hitler just "blitzkrieg-ed" around it by going through
Belgium.

They also formed an alliance with one another, and
wth the Soviet Union. They even practiced brinksmanship - a foreign policy where they
threaten war if a certain action is taken, gambling that he will not.  They did this
after Czechoslovakia was taken, and threatened Hitler with war if he invaded Poland. 
It's a way of trying to prevent war by threatening war.  It worked about as well as
appeasement did.