IB presentation done!

Finally finished my IB presentation,i've been working on it for 2 weeks,Anyway my presentation is about Nike's business in China,i am suppose to present something from any news article only that it needs to be a business between 2 countries,well Nike recently opened a flagship store in beijing,so i decided to present that.Now thinking if i should wear formal for my presentation?My lecturer said that i dont need to but it could be a bonus mark??