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Do a girl looking out the window at a night sky with a WW1 plane flying by then at the bottom write 'Star light, star bright, first star I see tonight, I wish he may, I wish he might, why won't my daddy go to fight? Her father let her down, don't let your children down. ENLIST NOW!'

I entered a competition to do the best WW1 propaganda poster with this design & won first prize! Hope it helps:)

A very influential and hard hitting propaganda poster used during the war was those that posed Children asking parents what they did during the Great War which had a massive emotional effect on people and encouraged them not to be scared and sign up. So maybe one that posed more on the expectations of the young to be looked after or protected because ask most parents who would they rather die for.....Country or their kids. probably more effective than glorifying the war especially later on like in 1916 when people realized that the war wasn't such a 'great' war and wasn't going to end quickly and particularly after the Somme when people became more discouraged to signing on.

How about showing a soldier leaving for war on a train, and his wife and children are there at the station waving him off. They are smiling and proud that their husband/father is going off to war to fight for King and Country. You can always have the children carrying little flags that they are waving. You can have flags of the countries involved in World War 1 around the edge of the poster. Perhaps a road sign that has Britain pointing one way and Germany the other way.

I am in the UK so if you are in another country then just change the road sign to your country.