If you have an insurance claim you should phone your broker first and report the loss. Then you should get a contractor to do what ever is necessary to ensure there is not further damage. For example if shingles blow off your roof, you should have a roofing contractor come and patch the shingles so that if it rains no damage occurs.

You should never do any repairs your self at the risk of getting injured.

Once a claims adjuster has come out to assess the damage she/he may suggest a contractor. It is the owners choice as to who their contractor is.

You want to make sure you hire a contractor that is reputable, provides a solid workmanship guarantee, takes the time to discuss your questions and that will do good work.