A visa stamp is a small document that is sealed into your passport by a US consulate abroad, which shows your visa class (F-1, J-1, H-1B, etc.).
To apply for a visa stamp, please contact the US consulate at which you will be applying. The US government has a website with links to all American consulates around the world, that can be accessed here: http://www.usembassy.gov/
Follow the visa stamp application instructions exactly as they appear on the consulate’s web site. Do not ask your friends what to do, read non-consulate websites or guess.
Visa processing times vary widely by consulate and time of year. As with the instructions, follow only the processing time guidance found on the consulate’s website.
At VCU, visa denials and delays are very rare. If your visa application is delayed or denied, please contact GEO as soon as possible for guidance.