I have just purchased a "new" home. There is some water damage to the drywall where the built-in shower meets the drywall. It appears as if water seeped out of the shower curtain and damaged the drywall directly outside the shower. I am not a handyman, but I can do a bit of mudding and sanding if that is what it will take. If it will take removing drywall and re-installing, I'll need to hire out. How do I fix the drywall?

For whatever reason I am unable to attach a photo even though it is in an acceptable format (I've tried JPEG, BMP, PNG).

Thank you!