20 year old student, looking for apartment in Vienna 19th district Feb-May

I am a student at Cardiff University studying French and German. I am currently doing my year abroad. At the moment, I am studying in Nantes, France, but in February I will be moving to Vienna to teach in a school from the beginning of February until the 31st May. I am looking for an apartment for one person, a studio or apartment with one bedroom. I would like to pay no more than 550 euros per month. 

I am a friendly, clean person hoping to improve my German language and would like to explore Vienna, so an aparment in a good location near local transport lines would be perfect for me!