Everyone residing in the United States with family members living in other countries knows how difficult it is to get a visa. Most Americans have no clue that many foreign individuals have very little hope of ever being approved for a visa. Nevertheless, those residing in the United States can help their family members in some instances. That is not always the case, but in some situations a relative living in the United States can help their family member be approved for a visa.
Write a letter to the consulate. Family members, especially U.S. citizens, have luck sometimes by writing a letter to their consulate on behalf of their family member. This letter should state that you as a U.S. citizen will care for your family member, provide them a place to stay and ensure they will not overstay their visa. Provide your name, phone number and address, and have it notarized.
Deposit money in their bank account. Many times individuals are denied visas because they don't have strong enough ties to their home country. Even though your relative may plan on returning, they must prove this. Having cars and homes in their name is a good starting point as well as a large amount of money in their bank account. They need to prove they can afford to travel to the U.S. and that they won't want to stay there upon arrival. You might be able to loan them some money to make their status appear better than it really is.
Help them understand the system. The way the visa program works is rather confusing. There are basic rules and there is discretion. What is most important is to make your family member understand the basics. For example, if a U.S. citizen's mother, brother and father all wanted to come visit him in the U.S., they would likely be denied. However, if only the mother applied, she would have a chance at being approved because she was leaving behind ties to her home country in her son and husband. It's confusing, but it makes the most sense for only one family member to try and visit at a time. Unless the family is extremely well off financially and there would be no risk in giving them visas.
Provide them with an invitation. Providing your family members with an invitation is sometimes enough for a visa application to be approved. This may be an invitation to a wedding, party, or simply to spend some time with you.