Hi,
I have read your requirement in which you have mentioned that you want your existing site should be more speedup.
I have checked the current performance on gtmetrix where the load time is 19.0S.
Relevant Skills and Experience
Following steps so we can increase the site speed:compression,caching,leverage browser caching,optimize images minify css and js,add expires headers,database optimization etc
Proposed Milestones
$50 USD - will make the speed under 4S with a great performance.