Where do I start? I need to copywright and register a .com name for my small online fashion biz?

I am fresh out of college and am wanting to start my own business, online selling my unique designs (I'm a fashion designer). I have a name I'd like to use for my business and I want to register the .com name to start a website .. how do I go about doing this? I also want to trademark / copywright my name so no one else can use it. How do I do this? Please help. Thanks so much.