If a student schedules an interview within that time, and still has not received the I-20, he/she should contact the school and ask for the I-20 to be emailed in time for the interview. If students wait to receive the I-20 before scheduling an interview, they risk not having enough time for visa processing if shorter than 3-4 months before classes begin.
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More than 73 percent of applicants receive their visas within 4-6 weeks. A student who applied the recommended 3-4 months ahead of the start of classes has a 93 percent likelihood of making his start date on time.

Another big mistake students make, they say, is coming to their interview unprepared (number 3 in Donahue’s tips, if you’re keeping track).

A student who does not show up for the interview with appropriate paperwork, and has no idea where or what s/he wants to study is not a credible student. Students are expected to have a certain degree of knowledge about their academic plans.

In addition to proving they are a credible student, applicants must show the consular officer that they intend to return home after their education. The Trinidad Express (in Trinidad and Tobago) has a regular “Ask the U.S. Consul” column, and a few years ago the Consul explained how to prove your ties to your home country:

The most important thing you need to know is that our officers are required by US Immigration Law, to assume that all applicants intend to immigrate and live permanently in the United States until they prove to the officer otherwise. This is the same at every Embassy and Consulate throughout the world, not just in the Caribbean, and certainly not just in Trinidad and Tobago.

What this means is that the burden of proof is on YOU, the applicant, to prove to the officer that you will return to Trinidad and Tobago after your visit to the US.

So what are ties? Basically a tie is something that will require you to return to Trinidad or Tobago within a reasonable amount of time.

Ties can be a variety of things, but, generally speaking, our officers look at personal, professional, and economic ties. Our officers do not use a check-list of requirements; instead, they try to learn as much information about the applicant, including things like his or her family situation, employment history, financial ability to pay for a trip, travel history, or plans for the future. Then, based on the ties that the applicant has shown, the officer determines whether or not the applicant is qualified for a visa.

An applicant also has to prove to the consular officer they have adequate financial resources to support themselves in the U.S.

Here’s one final tip from the visa officials in Riyadh, which might help you get your visa processed successfully and on time:

Many students do not properly fill out the DS-160 visa application form, leaving out crucial information that actually will delay their visa processing. Students should take care in filling out the form and answer all questions completely and truthfully. While some applicants choose to have a vendor fill out the DS-160, some vendors do a sloppy job of filling out the form which at best will delay the student’s visa processing or, in the worst case, could cause major problems.