3 months for basics is enough, some more for conversation level. But thats actually studying in Uni 5/7 and i do have language affinity. Your mileage may vary.
As for tips – Hanzi>all. You can speak with terrible accent and still be understood, you can ask people to repeat if you didn’t understand what they said, but if you can write or read – you’re dead 🙂
All IMHO.