A few options would be:

• Always pick the highest-voted answer. This relies on the asker either keeping this up to date as new answers get voted up, or just picking the highest voted after N days from the asking.
• Never accept an answer and just rely on upvotes for rep.
• Pick whatever answer the asker likes most based on whatever criteria he/she feels like (humor/accuracy/whatever-they-agree-with).

A few options would be:

• Always pick the highest-voted answer. This relies on the asker either keeping this up to date as new answers get voted up, or just picking the highest voted after N days from the asking.
• Never accept an answer and just rely on upvotes for rep.
• Pick whatever answer the asker likes most based on whatever criteria he/she feels like (humor/accuracy/whatever-they-agree-with).
• [Edit add:] Always accept Fishtoaster's answers because they are, by definition, the best.