NO, to register you neither need a sponsor nor have to be a member!!
You will essentially need membership only to get the Charter for which you have to have cleared all levels of CFA (not an easy task by any standards) and have the required acceptable 48-months investment related work experience.
To Register for CFA you have to meet the entrance requirements only, which is as follows (check at :
http://www.cfainstitute.org/cfaprogram/process/Pages/index.aspx )
* Have a bachelor’s (or equivalent) degree
or be in the final year of your bachelor’s degree program at the time of registration
or have four years of professional work experience (does not have to be investment related)
or have a combination of professional work and college experience that totals at least four years. Part-time positions do not qualify, and the four-year total must be accrued prior to enrollment.
If you initially enroll/register as a final year undergraduate student with a degree in progress, you may not register for the Level II exam until you have earned your degree, or obtained professional work experience that meets the program’s entrance requirements. .
* You will be asked to sign the Professional Conduct Statement and Candidate Responsibility Statement
* Be prepared to take the exams in English.
* Effective 1 January 2011: Have a valid international travel passport
You seem to be confused between registering for CFA Level 1 and getting the Charter!.