To get some practice editing you can use a sandbox. You can create your own personal sandbox for use any time. It's perfect for working on bigger projects. Then for easy access in the future, you can put {{My sandbox}}onyour userpage.
Please remember to:
Always sign your posts on talk pages. You can do this either by clicking on the button on the edit toolbar or by typing four tildes~~~~ at the end of your post. This will automatically insert your signature, a link to your talk page, and a timestamp.
Leave descriptive edit summaries for your edits. Doing so helps other editors understand what changes you have made and why you made them.
The best way to learn about something is to experience it. Explore, learn, contribute, and don't forget to have some fun!