You can improve your Afrikaans fluency by learning the 500 Afrikaans sentences on this site. (These all have audio by a native speaker).
Learning to speak the Afrikaans language well entails acquiring a large vocabulary, and also an understanding of the grammar. Afrikaans grammar is straight-forward compared to other languages. But you still need to understand or internalise it.
There are some grammatical explanations on this site, but really the easiest way of getting to grips with grammar is seeing the structures in use.
One way of doing this is through learning sentences - another of course being reading.
Learning the Afrikaans sentences on Easy Afrikaans, is particularly effective because of the simple grammar and day to day language used.
The sentences also contain many phrases that you are likely to need when speaking. For example, in the sentence Ek het dit twee weke gelede gekoop 'I bought it two weeks ago', the phrase twee weke gelede 'two weeks ago' not only gives you an idea of how to say 'three weeks ago', but can be used in many other sentences.
The sentences and phrases within them, can be used and combined in literally thousands of different variations, giving you a massive head start when starting to speak.
Learning complete sentences also has the advantage of increasing your spoken fluency. Words are normally spoken within sentences, and so it is much more effectvive (not to mention easier) to learn them in the same way.
There are five hundred Afrikaans sentences with audio, and these are composed of approximately six hundred words suitable for beginners and intermediates.
The crosswords use many of the same words used in the sentences, as do some of the vocabulary tests.
Have fun!