How do you manually focus accurately without a focusing screen?

I have a Canon 1000D and it doesn't come with a focusing screen. Sometimes my camera cannot focus in low-light. I'd like to manually focus, but without a focusing screen I haven't been able to do it accurately.

How do you manually focus accurately without a focusing screen? Or is the standard solution to get a focusing screen?

Answer

The 1000D has live view. If you're on a tripod, you could zoom the live view to 100% and use that to focus. This is going to be more accurate than a focusing screen anyway.

(Of course, the camera needs to support live view zoom, and I don't know whether that's the case for the 1000D).

Or you could turn on the focus assist, which will use the flash to illuminate the subject so the AF works.