i'm learning British English too and i see the best way to learn British English is to get used to listening to BBC news reports, 6 min English from BBC, and many other services the BBC offers, wish you all the best

I guess how you learn the British accent is by speaking and immersing yourself in it. I tried doing it and it totally sounded like a different person but my English and Filipino accent could sometimes interrupt the British accent during action. You could sometimes even would sound retarded but it would only sound like that if you force yourself out of your comfort zone on speaking, don't force the accent on to yourself and just flow using the British accent. I have never heard a real person speak in British but movies had them like Harry Potter or Tinkerbell and The Fairy Rescue. Then you can just repeat after them. I think there are lots of British accents on different parts of the UK. So maybe it is pretty vague but keep observing, you'll get there :) If not, keep on observing and listen. It is okay to make mistakes. You can simply ask them too.

I would think that you must listen to improve your listening skills. If you can listen to British YouTube speakers while reading a transcript of their words, what else are you looking for?

No I'm in Cairo, Egypt. but my work requires interacting with British customers everyday that's why I need to improve at least my listening skills ASAP.

Are you in the UK? Can you find a British friend who can help you?