comments:
You could get some colorful paper lanterns too hang from the tree. They're a bigger statement than just streamers, but you could definitely add streamers in like colors. Add some fairy lights to light up at dusk. Music is always a good idea. Beer pong is always a hit. You could do a twist on the game, like giant beer pong, using buckets of water and larger balls. You just drink a regular glassful of beer though. Water and splashing from the balls being tossed could be refreshing on a hot sunny day. We have a giant Jenga game that's always fun to play outside, but even a regular size Jenga game can be fun at a party. Here in the US, we also play a game called cornhole outdoors in the summer. I'm not sure if you have similar outdoor games across the pond.