If the website takes time in loading, then the user will not their time waiting for it. So, here are some tips to optimize the speed of your website:-
a) Minify the CSS and JavaScript files.
b) Plug-in should be avoided.
c) There should not be minimum or no use of flash in the site.
d) Nested tables must not be present.
e) Never use inline styles.
f) Take advantage of gzip.