That strongly depends on several factors:
A. If your relative is NOT a native speaker of English:
1). What is your relative's native language?
2). Where is your relative now?
3). What is the primary language in your relative's house?
4). Does your relative have any good friends who speak English?
5). What is your level in English?
6). What does your relative like doing?
7). Why does your relative need to learn English?
B. If your relative IS a native speaker of English:
1). Is there a specific area of English that your relative needs more help in (Grammar? Literary Analysis? Vocabulary building? Etc.).
2). What is your relative's goals?
In both cases, it is also important to know if your relative has a learning disability and if so - which one? Is your relative on the ASD spectrum? Do they have dyslexia? Etc.