In order to increase your shares, you have to sponsor other members. You can send individual transactions of 1 STEEM each, with the name of somebody to sponsor. Each of you will receive 1 new share. Alternately, you can send a larger transaction with more names.

In this example, @sneakyninja sent 3 STEEM with 3 names. Each of them received 1 share and @sneakyninja received 3 shares (in total 6 shares were created).

Enrollments are usually processed once a day, though there was some delay during the holidays.