Funny question to me as I’ve taught group fitness to people who can’t speak English and it certainly is educational! Here’s my best tips:
1. Know what their back ground in fitness and athletics is so you can use exercises that they may be a little more familiar with.
2. DEMONSTRATE EVERYTHING over and over again.
3. KISS principle: keep it simple. Regardless of if they know any English, this will make both your lives easier and keep the focus on persons goal.
4. Same goes for cuing: less is more. Simple~ up, down, in, out. Less words.
5. Be very visual. If they are ok with being touched I would definitely do so: for instance~if you want them to bend their knees, touch the back of them and then demonstrate the move again. Point 2 fingers to your eyes, at your knees, then back to their knees. Think of it as if they couldn’t speak at all 🙂 or hear.
Translators are nice, but rarely available and if so, I reserve those for the start of the lesson or end, to either summarize what I’d like for next time, or what we’ll be doing in the lesson.