How to improve your Quality Scores of your Adwords campaigns?

Some time ago, Google announced an update of the report of the Quality Score. A change - in their own words - little impact because the quality score would remain the same, only the reporting form would change. However, this is not quite the image we have at Harvest. And other agencies observe this. Because of the importance of good quality score is important to optimize it. But the question that remains after the change of Google: how do you do this?
Factors of Quality Score

What is Quality Score mean? As Google puts it himself, gives the quality score "an estimate of how relevant your ads, keywords, and landing pages for someone to see your ad gets". To optimize this score of keywords, it is important to know what factors are based on the Quality Score is determined by Google. The factors that influenced the quality score were, in order of importance:

1.      The click-through rate (CTR), also read "What is a good CTR?".
2.      The relevance of the ad compared to the keyword.
3.      The quality of the landing page (navigation on the site itself and transparency of the page).
4.      Many other factors play a smaller role, ranging from the historical performance of a campaign / account to the geographic location of the searcher. Some even claimed that the name of an ad affects.