What's the best way to proceed with labeling the dimensions, and the details? In other words, how do we add text explanations to a sketch drawing? Or should I just export plans and add labels through Canva? What's the best (free) way to do that?
Sketchup has a good option for adding dimensions - tools->dimensions. I have a video on that: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-J5S_GcvomKI.html. For more general labeling, I feel Sketchup falls a bit short but there is the tools->text option that allows you to place screen text or connect text to an object.
