Everyone's goal, disposition, and background is different, so there can't be one answer.
But here's what I think is crucial for me.
1. You make it enjoyable by picking a language that's most fun to you. Employ every method that might make it more interesting. If it never becomes interesting, then language learning is not for you and you are wasting your time.
2. Emphasize reading and listening, the "input". Reading, and next listening provides the basic nutrition for learning. If you get far enough in comprehension, speaking and writing gradually follows. In my mind this is the right way. Don't waste your energy trying to make butchered phrases too early.
3. Don't get swayed by all those learning aids and sites that promise quick results. Nothing can bring magic in language learning. Anything sounding too good to be true is exactly that, and only exists to make money off of you. Be patient and be ready for the long haul.