Negation in French: How to make negative sentences

To make a sentence negative in French you have to use two negative terms. The first one is "ne" (or "n' " if the word begins with a vowel) and the second one can be the most common "pas" or an other like "plus", "rien", "jamais", "personne".

Rien (nothing, not anything)
Personne (nobody, no one)
Jamais (never)
Plus (neither, not either)

When the sentence is conjugated in a simple tense, the first term "ne"/"n' " is placed directly before the verb, unless the verb is preceded by an object, in which case you should place "ne" before the object. The second term is placed directly after the verb.

Examples:
Je ne suis pas italien.
Nous ne l'aimons pas.
Elle n'écoute jamais.
Il n'aime personne.
Je ne veux plus manger.
Vous n'achetez rien.

When the sentence is conjugated in a compound tense, the first term "ne"/"n' " is placed directly before the auxiliary, unless the verb is preceded by an object, in which case you should place "ne" before the object. The second term is placed directly after the auxiliary.
Be careful there is an exception with "personne" that is placed after the verb.
Examples:
Ils n'ont rien vu.
Tu n'avais pas pensé à ça.
Nous ne sommes jamais allés en Afrique.
Elle ne l'a plus entendu.
Il n'a regardé personne.

"Rien" and "personne" followed with "ne" can be placed right before the verb, if used as the subject of the sentence.
Examples:
Rien n'est facile dans la vie.
Personne ne veut m'aider.