Boonex Dolphin H1 H2 Meta Description Alt Tag SEO Tasks

We are seeking a SEO Search Engine Optimization expert for our Boonex Dolphin Site to improve ranking on search engines: 1) add H1, H2 headings to every page 2) add alt tags to every image on the site(video, photo, group, event, classified ad thumbnails, etc) 3) add meta descriptions to all content on the site (photos, articles, classified ad, videos, q&a, etc) The task should be completed within and should be completed on time. Feedback will be based on performance.