The constitution says that...
Article 1- President
Section 1: A President must be elected every 2 months during the last 2 days of the month. Candidates must have a running mate prior to the vote. The candidate with the most votes at the end of voting will be inaugurated the following day, on the first of the month.
Candidates must have a running mate prior to the vote. As mentioned a running mate is the person that will run with you within the election. If you win the election, you'll be president and your running mate will be Vice President