The IELTS writing section Academic module is a challenging task. You need to master a good technique for this, and then the rest would be easy.
The first thing to take note of is that Writing task 1 is not the same as writing an essay in IELTS writing task 2. It is about writing Tables, Graphs, Charts, Maps, Processes, and Diagrams. Generally, you will have to write a report describing the information given, factually. No opinion on the information is needed. In the first sentence, you need to paraphrase the title of the graph using synonyms and adding a time frame if there is one. The second sentence would be the main trend of the graph where you need to describe what is happening overall. This covers the main changes that took place or the most noticeable differences over the whole period.
Your introduction will play a huge role because it will be the first part that will give a basic understanding of what you are writing about.
The next paragraph would focus more on the specific changes that have occurred. Make sure the detail in your IELTS writing task 1 based on the data given. The key is to group the data together to make sure you have a well-organized and coherent answer by identifying the similarities and differences. Then, decide which can be put logically into your body paragraph. You should describe the information contained, accurately and concisely, and follows a clear progression. Make sure you know a variety of structures to get a better score. Repeating the same style of sentences will show that you have a limited range of lexis and grammar.