To succeed in the second challenge of the 14 Days of Summer of Fortnite, you have to find the giant beach balls that are scattered across the map and bounce them.
Warning: only one bounce will be counted per match, and it will be necessary to make 5 bounces to complete this challenge. As you can assume, it is impossible to complete this challenge in one single match.
Here is the map showing where to find the giant beach balls. Be careful, these are their locations at the beginning of the game but players can move them.
Once you find the beach ball you have to bounce it. To do so, you just have to walk straight on it and bump it in. If it doesn't work, a pickaxe move also works very well.