Creating, editing, and promoting unique high-quality content is difficult and time consuming. If you are really serious about SEO and you are not getting expected result, then it would be better to hire an SEO expert.
SEO experts perform the are following tasks:
Code validation and clean up - Ensure that the code is search engine friendly and standards compliant.
Site Structure - Building a semantic structure/theme and ensure URLs are spider friendly.
On-Page optimization - Page Title, copy writing, Call-to-action, etc.
Quality link building - Securing one way links from relevant sites.
Keyword research - Building a list of key phrases relevant to your business.
Creating Quality Content - Building optimized pages around terms discovered through keyword research.
Off-Page Optimization - Managing Blogs, Press Releases, Article Submissions.
If you are confident that you have the required skills, then you can take care of all the above activities; otherwise it is worth taking help from SEO Companies or to hire any SEO specialist.
It is very difficult to choose a correct SEO expert or SEO company. However the following guidelines can help you in this activity:
Start searching through your friends and business partners.
Post your queries in SEO Forums to get feedback from the community.
Check other sites rank which they already have optimized.
Do not go for SEO companies doing automated submission.
Do not go for SEO companies doing Black Hat tricks.
Do not look for cheap SEO. But take care, high price also does not guarantee high quality.
Take guarantee if possible for a particular rank and any particular search engine.
User SEO Expert or Company name in Google to find more information about them.
Do not go just because of their fancy site and availability of good articles on their site.
Do not get fascinated by the testimonials available on their sites.
We can not list out all the factors here because there may be different situations and different views. You should be smart enough to think what's bad and what's good.