There are several ways to give instructions. One common way is to use the imperative.
Revision: formal imperative
When addressing a person using the formal Sie, we use the formal imperative. We make the formal imperative by putting the conjugated verb in first position, before the personal pronoun.
den Käse in Würfel.
den Käse auf die Pizza.
|Sie||die Pizza in den Ofen.|
In written instructions, e.g. recipes or operating instructions, the infinitive is sometimes used. In this case, we leave out the subject. The verb in the infinitive comes at the end of the sentence.
Den Käse in Würfel schneiden.
Den Käse auf die Pizza legen.
Die Pizza in den Ofen schieben.
Grammatical terms in German:der Infinitiv: The infinitive is the basic form of the verb that is not conjugated. This is the form of the verb that normally appears in vocabulary lists or the dictionary. German verbs in the infinitive usually end in -(e)n.