Just remember that "no" is the particle that indicates possession, so you need to show what it's possessing if you use it.

Sore can be used as a subject or object directly:

それを説明して下さい。
Explain that please.

Compared to:

その話を説明して下さい。
Explain that conversation please.

Using "no" to show possession can be used without indicating the possessed word with regular nouns, but not the kono/sono/ano words.

家のドアは大きい。
The house's door is big.
家のは大きい。
The house's is big.