The pronouns and the particles 
ci and 
ne are joined together, as a suffix, to the informal imperative.
For example:
"Guarda
mi" → Look at me
"Spegni
la" → Turn it off
With the irregular verbs 
dire, andare, fare, dare and stare, the pronouns and the particles 
ci and 
ne double the initial consonant, except for the pronoun 
gli.
For example:
"Di
mmi" → Tell me
"Da
cci una mano" → Give us a hand
"Mostra
gli il vestito" → Show him the dress
With the negative form of the informal imperative, we have two possibilities:
- the pronoun or the particle ci or ne is joined into the imperative as a suffix
- the pronoun or the particle ci or ne precedes the imperative
For example:
"Se non ti piace 
non mangiarlo" / "Se non ti piace 
non lo mangiare"
"
Non dirmi niente" / "
Non mi dire niente"