In fact, you can get visa by one of the following methods:
1. Go to Vietnam embassy to apply for visa: It takes 2-3 working days and you must travel a lot (normally, the embassy is located far from your house). It also costs much for travelling fee and takes time
2. Get visa on arrival. It takes about 5 minutes to apply for Vietnam visa application form and make payment. After 1-2 working days, you will get the letter of approval. With this legal documents, you can get visa once you arrive Vietnam international airports (Hanoi, Ho Chi Minh City and Danang).
Vietnam visa on arrival is the quickest and the most convenient way to get visa. It is also cheap and time saving