A well-written conclusion will help the reader focus on the information you have offered her in the body of your article. It helps the reader recapitulate and digest everything she has just been reading. The conclusion should also stimulate the reader to think further for herself about the subject you are writing about. For example, if you have written about different ways to feed the poor, in your conclusion you can stimulate the reader by mentioning that there are many other ways society can help the disadvantaged.
If your writing is more than just a couple of pages in length, it is almost impossible to sum up all its arguments in the conclusion. Instead, identify the most important points and arguments you raised in the body of your writing, and focus the reader's attention on them. This will help the reader understand what the most important aspects of your writing were and will help him better memorize those aspects.
Something experienced writers do to emphasize the message of their writing is tie the conclusion to the introduction. This will reinforce the way you have written your article and will keep the readers’ attention on the points you would like to put the emphasis on. However, do not use the same language in the conclusion and the introduction: Put the message you want to emphasize in totally different words.
Conclusions should point out broader aspects of a topic you have written about as well as propose a solution to any issues the writing might have raised. Quotations are always useful when used in conclusions, as long as they are relevant to the subject you have written about.