1. Eating meat, fish or eggs. These foods are saturated with the modes of passion and ignorance and therefore cannot be offered to the Lord
2. Gambling: Gambling invariably puts one into anxiety and fuels greed, envy and anger.
3. The use of intoxicants. Drugs, alcohol, and tobacco, as well as any drinks or foods containing caffeine, cloud the mind, over stimulate the senses, and make it impossible to understand or follow the principles of bhakti-yoga.
4. Illicit sex: This is sex outside of marriage or sex in marriage for any purpose other than procreation
You will likely find that your japa and kirtana are especially effective when done before an altar.
Setting up an altar at home means receiving the Lord and His pure devotees as your most honored guests.