When can you meditate effectively? It is when the raga doesn't continuously pull your mind outwards. Andegi, in a very nice essay, he say about monks. He says, when are you ready to renounce the world? When can you become a monk? If you stay away from the world and things and sit in an asham and yet think about those things, then you are not ready to be a monk. There are very few they, but there are such people.
The mind is very restless, turbulent, strong and obstinate, O Krishna. It appears to me that it is more difficult to control than the wind" - Bhagavad Gita (6.34)
"Lord Krishna said: O mighty-armed son of Kunti, what you say is correct; the mind is indeed very difficult to restrain. But by practice and detachment, it can be controlled" - Bhagavad Gita (6.35)
Inspired by these verses, Swami Sarvapriyananda provides invaluable guidance on improving our meditation.