My Website took to much time on First Byte

[Harish Kumar]

Hi there,

I have hosted my magento site on a shared hosting server onionfry.in,I think the theme I'm using took much time on processing the first byte..
Here's the result of my webpage...
Take a look here..

I have tried many of the methods like:
1) Enable cache in back end

2) Enable compiler

3) Merging Css/Js

4) Leverage browser cache

5) Image optimization etc....

Is there any way to minimize the first byte load without changing the theme..

Thanks in Advance!!!