Submit application forms well in advance!
It is well known that The U.S. Citizenship and Immigration Services (USCIS) is usually behind schedule. Applications frequently take up to three YEARS to process! Most green cards are good for ten years, so apply for your renewal well in advance. This is important to do since the authorities CAN deport you if you do not possess a valid Green Card. You should plan to submit your application / renewal forms early.
Apply for citizenship from within the U.S.A.
If you already have a green card, you should file for U.S. citizenship as soon as possible (if you want to stay in the United States). The majority of people can apply for citizenship five years after they receive their Green Card (three years or less if they have an American-born spouse). Having citizenship also makes your close relatives more likely to secure a legal status in the USA.
Notify USCIS of any address changes.
All immigrants who change their place of residency must notify the appropriate the USCIS within ten days of relocating. It is important to note that for every member of your family, a separate notification must be given (including children). You can print, fill out, then mail the AR-11 form (or just go to the USCIS website). If you have any pending applications, do not forget to send written notice of your new address to each and every USCIS office so they know how to reach you for any future correspondence.
File multiple immigration visa petitions.
It is possible to apply for a Green Card (or immigration visa) through the petition of a family member. You should check to see how many family members are eligible to petition for you. The more family members who are eligible the better chance you have in your application process. If one of the applications gets denied or takes too long, it is always good to have another option.
Be on time to all USCIS appointments.
You must ALWAYS be on time for all scheduled appointments with a U.S. consulate or embassy, immigration court, or the USCIS. You should always plan to arrive early to your appointments to ensure that your application process advances without delay (or upsetting the USCIS official). Applications are time sensitive, so it is beneficial to avoid any delays.
Don't violate any immigration visa laws
This is the most important immigration tip. Violation of laws can result in arrest and deportation. You should learn all the provisions of your immigration visa or green card. Learn all the laws (or as many as you can) in order to avoid any complications. Even small violations can result in your deportation.
Keep copies of all forms and documents sent to the USCIS
The USCIS is known for losing paperwork quite often. Send all correspondence with the USCIS via certified mail. Be sure to send these with a return receipt in order to prove that you sent these! It is also vital that you keep copies of all forms. These copies will prove that you filed the necessary paperwork.
Conduct research from reliable sources
There are common myths, rumors, and beliefs about immigration that can be misleading or incorrect. USCIS employees have been sometimes known to provide wrong or misleading immigration information. Even if you make a mistake based on what an USCIS employee told you, it is you, not them who is held responsible. You should do your own research. USAGC provides accurate and important information regarding the application and immigration process. Be sure to contact a representative with any questions you have!
Get help from legislators
If you are having difficulties, contact your U.S. congressperson. They are usually happy to make inquiries for you and can even encourage the appropriate agency to take action or get your application process moving for you.