Start with intermediate Dutch resources rather than beginner ones, because your passive understanding is already high. Focus on the systematic differences in grammar (like verb conjugations and word order) and false friends in vocabulary. A good approach is to use a textbook or online course aimed at A2-B1 level, combined with authentic Dutch media from day one.
As an Afrikaans speaker, you have a huge head start. You can likely understand spoken and written Dutch quite well already, especially in context. But the trap is assuming you can speak or write Dutch correctly without study. The grammar differences are small but important: Dutch has two definite articles (de/het), regular verb conjugation (including for jij/je), and a different word order in subordinate clauses. Vocabulary false friends like "winkel" (shop, not wink) and "pad" (path, not toad) can cause confusion.
For a textbook, look for a self-study course that covers the A2 level and emphasizes grammar explanations. Avoid books that start from absolute zero. Online, you can find free grammar guides that highlight Afrikaans-Dutch contrasts. For listening, start with Dutch news broadcasts (like NOS Journaal) and YouTube channels that speak clearly. For reading, try Dutch news sites or simple novels. For speaking, find a language exchange partner or tutor who understands Afrikaans and can correct your Dutch directly.
Common pitfalls: Using Afrikaans word order in Dutch (subject-verb inversion works differently), forgetting to conjugate verbs for each person, and using Afrikaans prepositions (like "in" vs "binne"). Also, written Dutch uses "ij" where Afrikaans often uses "y", and spelling rules differ. Practice writing short texts and have them corrected by a native speaker.
Concrete next steps: 1) Test your level with a free online Dutch placement test. 2) Get an A2-B1 textbook with grammar focus. 3) Start a daily habit of 15 minutes of Dutch news or a podcast. 4) Join a Dutch learning community that welcomes Afrikaans speakers. 5) After a few weeks, try writing a short paragraph about your day and compare it to a Dutch version.