They go through the official portal, following the instructions USCIS issues after the application and fee. Prepare files to the stated format, name them clearly, and keep a complete copy of everything uploaded together with submission confirmations. Treat any request to email documents to an individual, or to a third-party address, as something to verify first.
Keep one authoritative file set
Assemble a single folder that mirrors what was submitted, in the order it was submitted, with dates. When a later question arrives about a particular document, the answer should take minutes rather than a rebuild from scratch. Include passports, civil status records and translations, and note anything supplied in response to a specific request.
If several people work on the case, agree who uploads, so two versions of the same document do not reach the portal. Keep one authoritative folder that mirrors exactly what was submitted, in the order it was submitted, with dates. Where several people work on the case, agree who uploads, so two versions of the same document do not reach the portal and create a discrepancy nobody intended.
Documents go through the official portal following the instructions issued after the application and fee, so prepare files to the stated format and treat any request to email them to an individual as something to verify first.