The "idea, explain, example" format is a good way to organise your main paragraphs. Start with the main idea of the paragraph, explain it in more detail, then give an example.
A variation on this format is "idea, example, explain". Here's a paragraph that I wrote with my students about last week's topic:
Some art projects definitely require help from the state. In the UK, there are many works of art in public spaces, such as streets or squares in city centres. In Liverpool, for example, there are several new statues and sculptures in the docks area of the city, which has been redeveloped recently. These artworks represent culture, heritage and history. They serve to educate people about the city, and act as landmarks or talking points for visitors and tourists. Governments and local councils should pay creative artists to produce this kind of art, because without their funding our cities would be much less interesting and attractive.
Task: Analyse the paragraph. What role does each sentence play?