Think of it as adjusting three dials: pace, directness, and body language. On pace, slow down, use short sentences and common words, drop idioms, slang, and sports metaphors from home, and pause so others can process, especially when they are working in a second language. Rephrase rather than repeat louder when you see confusion, and confirm important points gently, since in many cultures people will say yes to be polite rather than admit they did not follow.
On directness, learn which way your host culture leans. In indirect, face-saving cultures across much of Asia and elsewhere, soften requests, avoid public disagreement, hear phrases like maybe or it is difficult as a polite no, and deliver criticism privately if at all. In blunt cultures, excessive hedging reads as evasive, so say what you mean plainly. Matching local formality, using titles, honorifics, and respectful forms with elders and officials, buys goodwill everywhere.
On body language, keep gestures small until you know the local repertoire, respect personal space norms, calibrate eye contact to what you observe, and moderate your volume. Underneath all three dials sits the real skill: listen more than you talk, watch how locals speak to each other, and borrow their rhythm. Add ten phrases of the local language, sincerely attempted, and most doors open.