The most practical way is to start a contest club and obtain a club call sign.
http://www.arrl.org/club-call-signs> According to the FCC rules, to be granted a club station license, a club should have a document of organization (minutes, bylaws, charter, etc.), a list of current officers (management), a list of members (at least four persons), and a license trustee designated by an officer of the club. An amateur can only be the trustee of one valid club station.
The club station can have multiple call signs assigned to it under one trustee but only one of the assigned call signs can be a vanity. A Club station may not hold more than one valid vanity call sign.
As long as the all the club station licenses display the same club name and use the same FRN (FCC Registration Number) and same trustee, the FCC views them as one club station with multiple call signs.
Additional information: Never associate a personal FRN to a club station license. An individual’s social security number and personal information are attached to their FRN. The club must apply for its own FRN number as a separate entity. <=