"Do not come here."
Translation:Não venha aqui.
When giving an order like "Do not come here", Portuguese doesn't (normally) use the simple present it uses the imperative mood. If you look at the conjugation tables for "vir" you'll see this form listed under "imperativo" (in this case under "imperativo negativo" because this is a negative command).
When giving positive commands like "Come here" you'll hear both "Vem aqui" and "Venha aqui" used interchangeably, although technically there is a difference: the former is the conjugation for "tu" and the latter is the conjugation for "você". Note, the "tu" imperative is exactly the same as the "você" simple present when used in a positive sense, but annoyingly, it changes to the same form as the "você" imperative with an added 's' when used in a negative command: "Não venhas aqui".
Is it this complicated in English? Some links: http://brazilianportuguese.wordpress.com/2008/07/14/imperatives-look-enjoy-dream/
Although that looks like a word-for-word translation, it doesn't work for a couple of reasons: the use of "faz" and "vir". When "do" is used as an auxiliary verb it is left untranslated as Paulenrique says earlier in this thread. For example, "Do you want a beer?" = "Você quer uma cerveja?"; and "Do not do that!" = "Não faça isso!".