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 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