Perhaps the most effective method is to watch videos. By doing that you can easily make associations and listen to the pronounciaton as well.
In case you have reached a certain level of knowledge, you can check out the articles on my site and train yourself.
Usually solving tests are not to interesting right? But you need to do it sometimes in order to review things and re-check your knowledge
I have found it really effective to learn a language by just reading signs on the street. Thus I make it available for you online!. Feel free to go through the cards and I guarentee that you will improve quickly. What else you need?