If you are foreigner wishing to enter Rwanda, getting you single entry visa is as simple as submitting you application to any Rwanda embassy in your country. This single entry visa is just $30 and last 3 months.
If there is no high commission for Rwanda in your country you may just log in to the immigration website of Rwanda (www.migration.gov.rw) download the application form and follow the guidelines. Submit and you will receive a confirmation email after. After this you will receive an acceptance letter which you will submit to the officials at you point of entry.
In case you want to stay in Rwanda for more than the given 30 days you are allowed to apply for an extension.
To get a Rwanda Visa you must have a valid passport, identification documents or any other acceptable travel document valid for least 6 months. Proof of payment of accommodation can be used as one of the evidence for you reason for visiting Rwanda.
You must have a Yellow Fever Vaccination Card in order to be allowed into Rwanda. Countries like Uganda, Burundi, Kenya, Tanzania, Democratic Republic of Congo, Mauritius, Hong Kong, Philippines and Canada can visit Rwanda without a visa. Also countries like Israel, USA, Australia, New Zealand, Germany, South Africa, UK and Sweden do not need to apply for the Rwanda visa in advance.
You may also choose to apply for the East African Tourist Visa which will allow you to visit Uganda, Kenya and Rwanda at a cost of $100. The country where you want you safari to begin from should be the one that issues this visa.
The application requirement for this visa is similar to the ordinary tourist visa. You can only apply for this if you are planning to visit any other East African Countries and you will freely move across all the boarders without an extra cost.