Adding the virama (್) below ದ creates the half letter ದ್ — it silences the inherent 'a' and allows this consonant to join the next one directly.
The halant form ದ್ appears in conjunct consonants and cluster words.
Watch the animated stroke order below. Each stroke is drawn in sequence — follow the arrows.
Stroke order animation via Wikimedia Commons, CC BY-SA 4.0.
