I’m sure you have found some differences between the gender that nouns have in German and in your mother tongue. This can be a little bit confusing, so you really need to learn at the same time the translation of every word as well as the “definit Artikel” that goes along with it. Just because the more grammar you learn the trickier it gets, it is essential to learn words and articles properly since the very beginning.
In my case, writing down every word next to its article many times helps me memorising them, but I know this can be very boring and it doesn’t work for everybody. An old technique is the post-it game, because it’s more visual and you learn unconsciously as part as your daily life.
It is very very simple, as you can see in the picture. Just get yourself a pack of post-it notes, write the name of the object in German and stick it to the object itself. In this way, every time you sit down for a meal you know you’ll be sitting on “der Stuhl” and your plate will be served on “der Tisch”.
You can increase the number of post-its after every lesson to learn the new vocabulary. Well, in case your flatmates don’t get mad at it!