If you are assembling a physical package yourself (such as for a passport application or a USCIS filing), the USCIS Lockbox suggests this order: (if required) on top. Payment (fee forms or checks). Cover forms (like e-Notification requests). Main application forms . Supporting documentation . 3. Tips for Self-Mailing
: You can get free Priority Mail boxes and envelopes at USPS retail locations or order them online for free home delivery. postoffice com
Instead of manually putting paper into envelopes, you can use online services that print, fold, and mail documents for you: If you are assembling a physical package yourself