When going through a loss, so much is happening, it is easy to lose sight of what measures need to be taken in reporting a claim.
First, you need to analyze the severity and cost of the claim. I say this because if it is a small claim, one that is less than or equal to the amount of your deductible, it may be better to not report it. This is what we would call "self-insuring". If you decide to self-insure, it is best to not report.
NOTE: if the claim is reported and the insurance company does not pay out any money, it will still be reported as a claim. It will still effect your record, even though nothing was paid out.
It is a great idea to assess the loss before calling to report. This way you can weigh your options. Often times, if the claim is small, you can save money by self-insuring, because the increase caused by reporting the claim could be more than what you paid out of pocket.
If you are currently doing business with an insurance agency, your agent is a great reference point as to what your best options are. Whereas if you call the insurance company direct, the claim will be reported. So lean on your agent for advice.
If you decide to report a claim, you will need to have information regarding the claim readily available. I.e. date, time, property affected, persons involved, damages, etc.
Once this information is given, a claims adjuster will be assigned to the case, to inspect the damages and figure up the payout, if any.