Listening and understanding
When you talk about speaking, you mean conversation, right? You say something, and another person says something. You listen to the person and you respond, and vice versa. To be able to understand, you need practice listening.
Listening corresponds to speaking, I already told you when we were talking about speaking that you must listen first.
Speaking
Most of the time when I we set a goal with my students, they say they want to be able to speak Russian.
You must speak and train your muscles to pronounce words of the Russian language.
Please note that reading and writing are not speaking exercise. To be able to speak, you must speak, you must open your mouth and pronounce words and sentences. Again, it reminds me of swimming — go ahead and swim. You can have a ton of good books about swimming, but they are not so helpful unless you jump into a swimming pool. The same is true here — open your mouth and speak!
What to speak? First I can recommend that you repeat what someone is speaking. It might be a recording. Some courses require that you listen to a lot of recordings; go with them!
Speaking is natural for a person. You listen, and you repeat — this is the most natural way of learning language. The only bad thing about it is that it is very slow. You need an incentive to succeed; I will talk about it later in this blog.