Hi!
For grammar points I created postings on a web page to explain in English how the construct works in both languages. I assign this for homework so that I do not need to cover it in class.

Before the web site, I used to create hand-outs that I distributed at the end of the class for the next class in which I was going to cover the concept. They read and worked with these at home. I used class time for discussions and practice in the TL.

If a really complex idea comes up in class that I think is critical for everyone to understand, and I know the TL charades are going to take too long or be ineffective (not worth the class time to work out), I take an ETO (English Time OUT) (no more than a minute or two) to summarize.

But I have them review the explanations and use the practice material before coming to class to minimize English in the classroom.