Reduce the number of requests.
Example:
http://www.gute-mathe-fragen.de/
It is down to only 11 requests (main site), from which are:
- 1 html
- 1 css file
- 2 js file (jquery by CDN)
- 4 avatar graphics
- 1 spinner graphic
- 2 design graphics
+ activate caching using your htaccess
+ Put everything in compressed files.
Then your site gets quite fast :) my site loads in 0,95 s.
Ah yes, and you should have a professional hosting provider. That has a very good reputation (it will cost a bit).