Create only high quality content
It is obvious, that trusted and high authority websites serve high quality content. Google can detect spelling mistakes, style problems and some common quality content patterns. Publishing good content encourages your visitors to spread it, “like” it, “+1″ it, etc., which also counts.
Always keep on adding new content
This depends on the niche and purpose of the website. It is always good to update your website periodically and keep the content fresh. You wont find any authoritative news websites, that are updated only once a month. If your website represents your business profile, contacts and a few descriptions it is a different case, but if you have ways to serve fresh and useful content – DO IT.
Create representitive profiles on Facebook, Twitter.
Most of the trusted people, companies have popular facebook and twitter profiles. In 2011 Google has announced that they have the ability to estimate facebook and twitter profile authority and this effects ranking more or less.
Trusted professionals and companies tend to have developed Linkedin accounts with many connections.
Sign up for Linkedin
Register with Google places
Physical location of business is always a sign of consistency.
Sign up for Google places
Register your domain for a longer period
This is a very minor factor, but if you are creating something serious, you do not plan to stop it after a year or two. Consider registering your domain for 3-5 years or more.
Get registered in serious directories
There are thousands of online web directories, but only a few high authority. Getting your business listed on these directories gives you a noticeable advantage.
Submit to DMOZ
Submit to Yahoo (Paid submission for commercial websites $299/year)
Submit to Business.com (Paid submission $299/year)
Link to high authority or related websites or do not link at all.
High authority websites rarely link to low quality, spammy websites and vice versa. Google uses this psychological law to determine ranking and calculate TrustRank.