These points come up again and again across all four skills. If you remember only 6 things, remember these.
1
Paraphrase is the central mechanism of the entire exam
The question never reuses the exact wording from the passage. Reading is really a synonym test, not a speed-reading test.
2
Answers appear in question order
True for Listening (all Parts) and Reading (except matching headings / matching information). If you find Q3 in paragraph 2, Q4 is definitely after that.
3
Misspelling = lost marks, even if you heard/read correctly
The most common mark-losing mistake in Listening.
4
Exceeding the word limit = lost marks, even if the content is correct
NO MORE THAN TWO WORDS means 1 or 2, not necessarily 2. Hyphenated words count as one word.
5
Never leave a question blank
IELTS does not penalise wrong answers. Guessing is better than leaving blank.
6
Underline keywords = nouns and verbs. Skip prepositions and articles
But matching keywords only helps locate the paragraph; you still need to understand the meaning to answer correctly.