How many times I have to undergo teeth whitening?

[Ashna2018]

Hi friends, I am fed up with the yellow color of my teeth. I am getting married in next August. Before that, I would like to get rid of this discoloration. My fiance also told me about this. He told me to try some cosmetic procedures. But before going to try such procedures, I made a try with some natural remedies. I used to clean my teeth with some special kind of toothpaste. But, it didn't give any satisfactory result. He again told me to undergo some treatments for this. I asked about the treatments to one of my friends. She suggested me a clinic in Whitby for undergoing teeth whitening treatment. Her tooth got chipped due to an accident and she consulted the emergency dentist at that clinic to fix her teeth. I am planning to take an appointment from there. But before undergoing the treatment, I would like to know more about this. How many times I have to undergo this treatment to get the desired result? Is it possible to complete with a single sitting? What are the dos and don'ts after this treatment? If anybody knows about this, please help me with your replies.