The position of nicht (not) in a sentence is actually quite simple and straightforward. You just have to keep in mind a few points and the positioning of nicht will (literally) fall into place.
Nicht is an Adverb: Nicht is an adverb, and so you will always find it either before or after a verb, adjective or fellow adverb. It usually precedes an adverb or an adjective, but likes to settle after conjugated verbs. (So think opposite of English)
Ich trinke nicht meine Limonade. - (I'm not drinking my lemonade.)
Nicht and Declarative Sentences: On the other hand, nicht likes to travel all the way to the end of a sentence at times. This happens most often with declarative sentences.
Sie arbeitet nicht.
(She is not working.)
A sentence with just a subject and verb.
Er hilft mir nicht.
(He doesn’t help me.)
A sentence with a direct object (mir).
The same applies with simple yes/no questions:
Gibt der Schüler dem Lehrer die Leseliste nicht?
(Is the student not giving the reading list to the teacher?)
Nicht and Separable and Compound Verbs: With verbs, nicht will bounce around a bit depending on the type of verb:
Nicht will be positioned right before a verb prefix in a sentence containing a separable verb.
Wir gehen heute nicht einkaufen.
(We are not going shopping today.)
Nicht will be positioned right before an infinitive or infinitives that is part of a verbal combination.
Du sollst nicht schlafen.
(You should not sleep.)
Du wirst jetzt nicht schlafen gehen.
(You are not going to sleep now.)
Nicht and Adverbs of Time: The adverbs of time that have a chronological logic to them, will usually be followed by nicht. These are adverbs such as gestern (yesterday), heute (today), morgen (tomorrow), früher (earlier), später (later).
Sie ist gestern nicht mitgekommen.
(She did not come along yesterday.)
Contrarily, adverbs of time that do not have a chronological logic to them will be preceded by nicht.
Er wird nicht sofort kommen.
(He will not come right away.)
With all other adverbs, nicht is usually positioned directly before them.
Simone fährt nicht langsam genug.
(Simone doesn’t drive slow enough.)
So in a nutshell…
Nicht will usually precede:
- adverbs of time that cannot be organized chronologically
- all other adverbs
- separable verb prefix
- verb infinitives
- prepositional phrases
Nicht will usually follow:
- Adverbs that can be organized chronologically