The link that was posted is good information on how eggs are graded.
For the most part, if the egg is not cracked, dirty, or stained, and you know that it has been freshly laid, then it's going to be Grade A or better. You can follow the guidelines and candle them, but you'd be hard pressed to find any that weren't Grade A due to internal conditions.
You don't have be government certified to grade eggs or to sell your graded eggs as such, but if you hold a state permit to process and sell eggs, a state or USDA inspector may want to check your work during inspections. The only marking that you would use would be "Grade A" as most small producers wouldn't try to separate out Grade AA eggs and in most states it is illegal to sell Grade B eggs as shell eggs to the consumer.
Only egg cartons that are stamped "USDA Grade AA" or " USDA Grade A" have been graded by a USDA inspector through an optional service that the USDA provides to processors who are willing to pay for it.