Freely; without restriction; having complete control or mastery over something.
彼は日本語を自由自在に話せる。
He can speak Japanese fluently and with ease.
そのソフトを使えばデータの表示を自由自在に変更できる。
With that software you can freely change how the data is displayed.
幼い子どもが庭を自由自在に走り回っている。
The young child is running around the yard freely.