How to use properly conjunctions in a French essay?

In French we have two types of conjunctions. The coordination conjunctions link words or groups of words together using words such as: mais, où, et, donc, or, ni, car. They show union, consequences, conclusion or alternative. After that we have subordination conjunctions who link two propositions together, the main one and the supporting one. You can easily recognize them with words such as: lorsque, dès que, tandis que...