by practicing them over and over and over.
When I was new to the world of homeschooling, and pedagogy in general, I heard about the term "teaching to mastery," and it perplexed me. The idea is that you teach something until the student understands and retains it. You test as you go along, but if the student doesn't score highly on any given test, you adjust your teaching style and go over it again. What perplexed me was that there were teachers not using this technique.
It makes sense in a homeschool situation. Or, in other words, the reverse makes no sense. There's no reason I would, say, teach my child fractions, have them be confused and doing them all wrong, and then say, "Welp, that was all the time we have for fractions! On to geometry. You get a fail on fractions." I wouldn't hold my child back a grade in homeschool in some punitive sense, and, conversely, there's no time pressure to move up at a certain pace. We can speed ahead of things they've got down pat, and slow down for the more frustrating bits.
But then I remember my experiences in school, where teaching to mastery was not the norm. You kept up — or you flunked out. I was strong academically, so my two personal examples were in art and physical education. Fortunately, both were graded more on effort than skill, but I remember being criticized in art class more than learning how to complete assignments. In P.E., I remember being ignored most of the time. I wasn't worth bringing up to scratch, I suppose.