Turkey requires visitors from certain foreign countries to obtain an electronic visa before their stay. You can apply for a visa through the official e-Visa website, https://www.evisa.gov.tr/en/. While applying, you will be informed on whether you need a tourist visa for your stay depending on your country of citizenship. We advise you to apply for a visa at least a month before the conference.
All relevant information regarding the visas can be found on this website, https://www.evisa.gov.tr/en/tour/.