The speaking and writing parts are more subjective.
I'll start with Listening:
The listening part tests your ability to get information to follow a conversation or narrative and answer questions based on that.
You need to be familiar with the accents and also understand the questions being asked. I recommend that you read the questions to anticipate the responses and follow the conversations.
If you miss what was said in a conversation pertaining to a question, just skip it, as it can throw you off for the entire passage. The recording would be played just once so move on.
I recommend you practice at least for 4 full Cambridge listening tests and score them before the exam. If your performance is not satisfactory, practice more.
Reading:
The reading section tests your ability to extract information from a written passage, document or narrative. You may need to alternate between reading the questions and the passages a lot of times.
I had a challenge identifying the difference between false and not given initially when I started practicing.
I recommend you practice as many Cambridge passages as possible to get an proper hang of the pattern of questioning.
