Rose
Once she found a water purifier she knew these games would be games where purified and good water would be scarce and the chances of dying increased within a few days. Suddenly she wished she had a large backpack, surely it had more things in it to use. Except she didn't have it.
She started to rest a bit. She made sure she was on a wide branch and wouldn't fall while sleeping. She then made sure to secure and hide herself and supplies with a branch and leaves that she put on top of her. Weird or not camouflage could help. And with the only bow and arrows she could win this maybe. Only if she was cautious.
She closed her eyes only to be awakened a few hours later. No tributes in sight or hearing range. Yet she didn't make a fire. Fire! That could help her win this she realized. Heat was the natural enemy in this arena, make you thirsty and sweaty but this beautiful elements could help her...
Coal
He saw a cliff after an hour of walking. He looked down and picked up a rock. He threw it out and at what he thought a force field could be hiding. He got closer then looked down. A steep way down to a jungle below. He wondered if they could go down to the jungle and of it'd be safer with pure water down there. Instead of climbing he decided to lighten his load slightly, he found some bread in his bag and he pulled off a small chunk and ate it. Not wanting to waste things he closed his bag up. Ready to see if climbing was an option.
(Can the tributes go down the plateau or does the force field prevent it)