What are the best methods to practice perspective drawing? It’s something I have difficulty with, especially in character/concept design. I know the main answer would probably be just to practice, but are there any tasks specifically designed for this.

And does anyone know of art classes in London (part time or shot) where this is the focus? I plan to study illustration next year, and I recently saw a shot course in Life Drawing for Animators so I’m sure I’ll learn this there but am looking for something to get me on my way and to help my portfolio.

Cheers