Do you have students who are dead set on speaking with a particular accent? If you do or if you’re one of those students then read on.
My question for all of those students is WHY?! Most of the world’s English speakers don’t speak with an American or British accent. Plus within English-speaking countries, accents vary from region to region.
When I ask my students who they speak English with, it is usually people from various European countries whose L1 isn’t English like Germany, Switzerland, Italy etc. So then why care about accent?
This always gets them thinking and some get the idea and conclude that they should instead focus on making sure their pronunciation of words is correct and clear instead of trying to speak with a particular accent.
Of course, there are always a few who persist in their quest to sound British. For those students, I tell them to be a parrot. Watch a show or movie or YouTube clip, choose a character and act like a parrot. Repeat everything they say, immediately after they say it. Better yet, watch something with English subtitles and read along with the character. It never fails, they feel foolish but end up sounding like whatever character they chose to shadow. Test it out with whatever language you’re keen on practicing and with whatever accent you want. You’ll be surprised at how quickly your accent will change (even if the change is short-lived).