Points are awarded for skirmishes, and the number is directly tied to the achievements in the given skirmish.
Points can be won for:

• participation [1 point]
• guild's victory [3 points]
• defending the tower - when we have a better score [6 points] or a worse score [4 points]
• the 'Champion' title [3 points]
• the 'Charger' title [3 points]

You can obtain max. 16 points for one skirmish.