How should native English speaker communicate with non-native

Slow down English speaking speed, 100 words/min would be suitable
Avoid idioms and acronyms
Avoid metaphor or proverbs
Avoid involving local news and celebrities, even something familiar by Asian, since the pronunciation may differ, causing confuse
Speak clearly and pronounce your words correctly
Please speak loud enough to be heard clearly when direct communication is needed.
If possible, use simple words instead of complex ones
Encourage non-native to interrupt when they cannot follow