Just because you are not having a conversation with anyone does not mean you should not be pronouncing individual words and sentences out loud on your own. Constantly. Every day. Babies babble for months before they utter anything close to a “word” and then utter approximations of what they hear, with positive feedback from their family for their increasingly more accurate utterances. In order to “speak,” you have to practice making the sounds of individual words and of short sentences on your own, out loud. If you haven’t been doing this, then I strongly recommend that you start right now. Read out loud every lesson that you’ve been “just” listening to and/or reading silently. This is critical to train your voice muscles and breathing and to practice pronunciation, intonation and phrasing. Doing so also helps with listening comprehension since in order to imitate something it is necessary to pay closer attention to HOW something is said.
At first, do not try to understand the meaning of something and imitate the pronunciation at the same time as that is too difficult. Instead, choose something that you already understand when just listening and try to imitate the native speaker one short sentence at a time or only a couple of words at a time if you can’t handle a sentence yet. Make this part of your daily routine so speaking is no longer strange/odd/scary. Remember, no one is listening. No one speaks perfectly at first. NO ONE. It takes practice and the more you do it, sound combinations that once were difficult will become easier.
Once you are comfortable saying short simple sentences in private, I suggest USING them throughout the day to describe things in your environment. For example, when I started in Russian, I described out loud whatever I saw in real time. When I was driving the car in the country (very little traffic) I said, “black car” “white car” blue sign", “green sign” when these appeared on the road. It was a game. When I learned verbs, I added, “I see a black car,” “there is a green sign.” In the city, I said the names of things I passed on the street as I was walking, at first just nouns, then nouns plus adjectives, then short sentences. (If people are nearby you can “say” these things in your head but practicing out loud is much more effective.)
I also recommend writing out short sentences and/or keeping a journal of what you do. Use whatever words you know and want to know right now. For example, Today is Monday. It is sunny. . Today is Tuesday. it is sunny. I am drinking coffee. Today is Wednesday, it is cloudy. My cat sits next to me. After you write a sentence, read it out loud, then try to repeat it without reading it (which is not so easy at first). You don’t have to write a lot but write something that is meaningful to YOU at the moment. (I want to talk with a tutor.) One advantage of writing a journal is that you repeat some vocabulary over and over and are using it in a meaningful context which reinforce vocabulary and grammatical patterns. (For example, I did not try to memorize the days of the week all at once but instead wrote the day of the week at the top of the page each day, and so learned them effortlessly.) Incorporate new vocabulary and grammatical constructions that appear in your lessons on LingQ in what you write as appropriate and natural. The more you acquire words that genuinely apply to your immediate life, the easier it will be to use them every day in short sentences. Practice saying out loud what you are doing as you are doing it. For example, I am going to the kitchen to make coffee. Where is my cell phone?
When you are comfortable saying simple, short sentences by yourself, you will be able to take the next step and schedule a lesson with a tutor. I suggest scheduling a short session (not more than 30 minutes) and that you write out and then practice out loud a short description about yourself, adding things as you would naturally. Even so, just sitting in front of the Skype screen is stressful . Don’t be surprised when you forget things that you thought you knew which is why I suggest practicing a LOT before you have your first session. Also keep in mind that in a Skype session not only will you be speaking, but you will have to understand what the other person says and that is not easy either. How do you get to Carnegie Hall? Practice, practice, practice!