It’s apparently the first sign of madness, but it’s also a great way to help you practice speaking without the pressure of getting it right or not. Talking to yourself in English (on your own!) lets you experiment with words and sentences, but more importantly, your pronunciation. How do you sound when you speak? Practice saying words until you feel comfortable with them. Practice saying new words in different combinations. Practice different pronunciations! All this practice will help you feel ready for when you will need to say these words in a real-life situation. It’s also a well-known fact that speaking helps you to remember, so your ability to recall (think of) words when you need to will increase as well as your confidence.