I am a foreign salesman, often met different country's friends,what bothers me is that sometime I couldn't get what they mean, and some customers speak quickly is also hard for me,I really want to improve my oral,hope friends can help me and give some advises
Ask them to slow down and speak clearly.
This is exactly what any native English speaker will do. You can do this too! :)
No worries. Sometimes native english speakers can't even understand each other when it comes to different accents.
yes I agree with Hamza and Peachey.
To Understand what native speaker said when they talk quickly , you need to improve your listening skills , and to do that you need to listen As much as you can to english conversation ( I always watch tv series ) . beside studying How they reduce and link words together ....etc. you can check this youtube channel it's very helpfull ( Rachel's English : https://www.youtube.com/playlist?list=PL27A5D7DE7D02373A )
I'm not a native speaker or fluent, but I found that this is a good way to improve my English , Hope that it will help you too .