How would you assist someone with learning another language.
How would you teach a language?
I would practice with them for an hour a day, with specific topics on certain days. Language is both knowledge and skill, but I know a lot of people who never get good because they don't use it as often as possible. So they never develop the skill. Now, if you keep practicing the wrong things, you'll never get better either, so it's best to practice with someone who can correct you. I'd do this with patience, respect and no judgment.