Pronouns with Present Gerunds
In Italian, when you use a standalone present gerund (verbs ending in -ando or -endo, meaning "doing," "observing," etc.), object pronouns attach directly to the end of the verb.
This applies to direct, indirect, and reflexive pronouns. Instead of placing the pronoun before the verb, you glue it to the end to form a single word. For example, coordinando + li becomes coordinandoli (coordinating them).
Pronouns with Past Gerunds
The past gerund describes an action that was completed before the main verb, usually translating to "having done" something. It is formed using the gerund of the helping verb (avendo or essendo) followed by the past participle.
When attaching a pronoun to a past gerund, the pronoun always attaches to the helping verb (avendo or essendo)—never to the past participle. For example, avendo + lo + ripetuto becomes avendolo ripetuto.
Reflexive Verbs in the Past Gerund
Reflexive verbs always use essere as their helping verb. In the past gerund, the reflexive pronoun attaches directly to the end of essendo (e.g., essendoti).
Remember that because the auxiliary is essere, the ending of the past participle must agree in gender and number with the subject.