You have to understand the motive your blog. Whether you want to create a personal or a business blog? It will help you to make clear your vision to make further proceedings. If you will not be able to identify the goal of your blog, you will find it very difficult to hire a good writer for it.
After assessing the objective of your blog, you have to create a list of skills which you want in your writer. The most common skills which a good writer possess include expressive communication, research skills, precision, time management, attention to detail, marketing skills, SEO expertise, and knowledge of the industry and markets.
After deciding what kind of skills you want in your writers, you can start you search. You can advertise on various jobs related websites that you want to hire writers for your blog or you distribute pamphlets and brochures in schools and colleges.
The most important thing about hiring a writer is to decide how much you are going to pay to him. It all depends on your own earnings. It will be quite stupid to hire a writer who demands more than you earn.