If your meta tags are well stated as per search engines preference then its great as if not then do check those and correct it. Since you know SEO then it will not be a mammoth task to gain top rankings in Google. though SEO has many processes using which you can get the desired rankings but as an easy and on going process I would suggest to follow the process below:
1. Create a blog site and post an informative blog daily on your site's niche related areas and bookmark it and do share it in social medias
2. Post few articles (informative and unique) in top 5-6 article directories, include HubPage and Squidoo in the list
3. Create accounts on top webmaster forums and you site niche related forums and contribute yourself effectively
4. Always be updated on social medias and do reply your networks and followers to gain more
Please remember one thing that uniqueness and quality is the only key to success now.
Above mentioned points are easy to follow and less time consuming so you can perform. All the best!