The advantage is that you save 30-50% on your vacation compared to rack rates from Disney.
The process is not difficult you need to find an owner with aulani points who wish to rent. To do that you may look in the rent/trade board here on DIS.
Another option is to go through a rental company, but they rely on finding an aulani-owner who wants to rent. Since the rental companies take a cut you might have more luck using the rental board here on DIS.
Have in mind renting points also have some restrictions most owners do not allow a refund/cancellation if you can't go. This would be the same if you used the rental companies.