One of the best ways you can improve your pronunciation is to regularly listen to native English speakers who speak with a clear and are easy to understand accent. Below are some links to videos of British newsreaders and journalists. Observe them carefully and try to mimic their sounds.
George Alagiah
Katty Kay
Mishal Husain
Sophie Raworth
Fiona Bruce
Michael Buerk
Emily Maitlis
Mary Nightingale
Kate Silverton
Julie Etchingham
