Read out loud. Record yourself and listen back. First we hear then we speak. Input then output. Listen to TED talks.

Talk to yourself every day. I know, it sounds weird but works. Choose some topic that is interesting for you, read some articles about it, make some notes and then talk to yourself aloud.

Have you looked into the practice technique called "shadowing?"

There are many things you can do: - reading is very helpful for building vocabulary ready for speaking - studying pronunciation features (also called connected speech) - having fun with tongue twisters