While watching a movie, imagine that you work in the film industry and are going to give the sound of your voice to the actors. You need to make some preparations. What I want you to do is:
Pick a very short segment, one or two minutes.
Listen to it very carefully.
You may write down a few words that you want to practice.
Watch the scene few times.
Then turn the sound off and try to reproduce the dialogue or monologue from the video.
Can you do this? Good.
For beginners it is very good to repeat after the recording: a movie, a tape, radio etc. Just repetition helps.
You can turn your grammar exercise into a speaking practice by just recording everything with your voice recorder.
As I always say: Speaking requires speaking. You must open your mouth and SPEAK. Though reading and other exercises can help improve your language, it is speaking that helps you develop a vocabulary.