That seems like a big difference between the two scores. Did you have an off day? I hope you will get the scores you are aiming for.
I’m sharing some strategies I found useful -
Reading - scan and skim, If you are trying to read every word and understand the details it’s not going to help with time management. More often than not the questions can be answered without having to read the whole thing.
Also, look for transitional words that show whether the text is being supported or contradicted - for example if you see the word “however” or “contrast” you know the subsequent sentence will be contradicting the previous sentence.
Listening - read ahead. I didn’t need 30 seconds to read questions or review my answers after every recording so I used it to read ahead and see what the theme of questions is for the next section. This helps me stay ahead of the speaker. Also it’s okay to miss one or two questions. When you know what the next question is about you will know when to move on from the previous one.
Speaking/ Writing: structure, structure and structure. I watched E2 IELTS videos and that’s all I needed. When you have the structure in place such as opening and closing sentences and paragraphing, you make it very easy for yourself to simply fill in the details and write a good essay.
I hope you will find this useful and feel free to ping me if you have any follow up questions. Good luck!
I leave you with this -
"Impossible is just a big word thrown around by small men who find it easier to live in the world they've been given than to explore the power they have to change it. Impossible is not a fact. It's an opinion. Impossible is not a declaration. It's a dare. Impossible is potential. Impossible is temporary. Impossible is nothing."
-- Muhammad Ali