IELTS Listening gives you about thirty minutes of audio in four sections, and every recording plays once. There is no rewind, in the test centre or on the computer-delivered version. That single fact should change how you spend the quiet moments the test gives you.
Before each section you get a short pause to look at the questions. Most students use it to read the questions once, politely, the way you would read a menu. That is not enough. Use it to decide, for each gap, what kind of thing is missing: a number, a name, a place, a job, a date, a plural noun. You are not guessing the answer — you are narrowing what your ears are listening for from "anything" down to "a number with a decimal point" or "a street name".
The second thing to do in that pause is to notice the order. The questions follow the order of the recording almost without exception. If you are hunting for question 14 and you hear something that answers question 16, you have already missed 14 and 15 — and the useful response is to let them go and lock on to 16, not to keep digging for what has passed. Losing one answer is one mark. Losing your place costs the rest of the section.
Third: read the word limit and obey it exactly. "No more than two words and a number" means a three-word answer scores zero even when the content is right. Students lose more marks to the instruction line than to the audio.
One more habit worth building early. When you hear the answer, write it down immediately in rough form and keep listening — do not stop to make your handwriting neat or to second-guess the spelling. The recording does not wait for you, and the next question is usually seconds away.