Make your editor help you

While the above is funny, using a good editor, and using it effectively, usually prevents such situations. A good auto-completing editor isn't necessarily to help one type faster - it is most helpful for the context sensitive documentation that it provides. It brings documentation closer to the act of writing code, and saves the context switch introduced due to Alt+Tab, F1 or any other documentation invoking key-binding.

Like so -

If you haven't found out how to make your editor do this, you probably should.