When learning a new language, it's easy to start deceiving yourself into waiting to use it. But why would you wait when there are so many good reasons for using it now, and so many interesting ways you can already use what you know to help you continue practicing and learning!
Confidence doesn't come from study, it comes from practice. It might be at a restaurant, while you're shopping for groceries, or just listening to the radio. You can practice your language and vocabulary while you're learning the history of a city you already know. You can even be practicing your vocabulary while you're counting change or dialing a telephone.
The point is that langauge is a means, not an end, and you need as much practice as you can get. You don't have to know everything before you start talking, because you'll find that there are always other ways to say what you need to say.
The more you use it, the more you will connect with the language, and the sooner you will start to change the way you think. The process of learning a language isn't a race, but if you just stop being so self-conscious, you'll find that you can learn a lot in just one month!
Stop waiting for a day that will never come
Don't wait until you're a master of your language. With a little creativity, you'll find you can say a lot more than just the words you know. Don't be one of those people who claim to know 60,000 words of Russian, but still hesitate to use it. I know only about 4,000 words of Russian, but I have meaningful Russian conversations literally every day, and it was more than enough for me to survive without English on my visit to Tashkent.
No amount of statistics or words or lessons is going to one day be the magic number, past which you feel confident. Confidence only comes from use. Everyone has to make their mistakes. The ones who make those mistakes sooner become confident speakers faster.
Just get out there and do it.
Want to see my favorite language resources and courses?
I listed them here.