Avoid the Crooks
If any of the following people try to counsel you about immigration matters, be wary.
Notary publics or notarios - They're licensed to perform only a select few administrative tasks, like authorizing signatures. They can't represent you in court or before USCIS.
Workers at unauthorized non-profit organizations - The Board of Immigration Appeals (BIA) approves people at certain organizations to help you with immigration matters. If they're not on this list, don't work with them.
Immigration "consultants" or travel agencies - These people likely have very little actual education about immigration law.
Take extra caution if anyone makes promises that are too good to be true, seems overly insistent about taking your money, or claims to have an "in" with USCIS or immigration officers.