Guardianship is a timely and costly process. One must file an application with the county court or statutory probate court in the county where the individual resides. An attorney ad-litem and possibly a guardian ad-litem will be appointed. A doctor's letter, certifying that the person is incapacitated is also required. That, unfortunately, is just the beginning and there aren't really many statutory aids to make the guardianship process less costly.
You might consider alternatives to guardianship, i.e. durable power of attorney etc. It's difficult to advise you without knowing more details, but guardianship typically is not the first choice when dealing with an incapacitated person. It is certainly necessary in some instances, but be sure that a guardianship is what you need. If you have any questions, I would be happy to answer them.