You must generally demonstrate the following: Your Intent to depart at expiration of requested stay. You Must show employment, family, social ties to residence abroad. This type of visa is for coming to the U.S. to visit and have a vacation. The B2 Visitor Visa is usually denied because you cannot prove your intent to get back to your home country from the United States. The B-2 Visa does not need prior USICS approval, but only from the U.S. Consulate.
Applying for a B1 or B2 Temporary Visa in Los Angeles
A B-1 visa permits a person to come to the United States temporarily for attending business meetings and trade shows, buying goods, or conducting research or other commercial activities. Foreign nationals with B-1 visa are usually admitted for a smaller time period. Admission is usually for a few weeks to a few months. It is difficult to the the green card directly from this visa. Only when you cannot get a visa waiver would you need to get the B2 visa. See some more specifics on the Tourist Visa
You May require posting of bond with Regional Director at port of entry. You must have permission to enter foreign country at end of stay.
You must show adequate financial arrangements (including resources for traveling and staying in U.S.) to carry out purpose of visit. You must include this in your visa application.
You should show you have money or proof of support from friends and relatives in U.S. or abroad if your going to come here on the visitor visa. USCIS and the U.S. Government wants to ensure that you do not have to work illegally to make ends meet. They must show that you have a source of funds you are able to rely upon.
You should show there are ties sufficient between sponsor and applicant to ensure support. If your going to get an extension, be sure to properly do the B1B2 extension letter.
You should provide documentary evidence showing all the above. That means showing your intent to return to your home country as well as showing ties, assets and families in your home country.