One of the biggest mistakes that students tend to make in their endeavor to improve their pronunciation is that they focus too much on their output rather than their input. They can perhaps put too much effort into correcting their own pronunciation before taking in the sounds of native English speakers. Both output and input are an important part of the feedback loop, but there needs to be a balance.
Understanding how we create each individual sound is only one part of the process. We also need to immerse ourselves in the natural rhythm of British English as much as possible. This is why it’s much easier to develop natural pronunciation, intonation and rhythm when living in an English speaking country.
However, you don’t have to surround yourself by living breathing native English speakers. One of the best ways of achieving this is by listening to audio books. Audio books tend to be narrated in a manner that is clear and easy to understand. Unlike TV shows and films, there are no visual cues and there is less distraction.
It doesn’t matter if you can't understand everything. Just sit back and immerse yourself in the sounds and carefully tune your ears to the voice of the narrator. Over time your mind will gradually become accustomed to the natural rhythm and become better able to distinguish the different sounds of British English. This process will help you reinforce everything you have previously learned in studying pronunciation.
Here is list of narrators on audible that speak RP:
Find a narrator you like, and a topic that interests you. Set yourself a goal of just listening for an hour a day. You'll be surprised how much progress you will make within a month. Click on the link below and start listening to some audio books.