It's easy, just design and engineer your main page in such a fashion that people will click beyond it into rest of your site.
If you are like a lot of webmasters you're losing a significant number of visitors as soon as they get to your front door . The Main Page on any site is doorway to rest of content of that particular site. But, BIG question is ....will door open? Will visitor turn knob and push through main page to see what's really in there?
We faced this situation recently. We had what was a very pretty web page. That's not just our opinion, many visitors commented very positively on look of main page. Some even went as far as to copy design completely and place it on their own page (but that's another story). The problem was that a good percentage of visitors never went beyond main page. Something had to be done, and done fast.
Following is what we did to dramatically change click through rate on our site pages. After implementing these changes we saw a 200% - 300% increase in our internal traffic.
1) Tighten up on load time.
The graphics files got reduced and used more efficiently. Some of nonessential copy got turfed too. We also took out virtually all outside links from main page. The result is a sleeker looking page that is more efficient in delivering message about rest of site.
2) Ease of Navigation.
All main category pages are clearly listed on sidebar. Each category page is a site unto itself with it's own navigation features and links to all other site categories are still listed on sidebar. This repeated but tasteful use of same links and graphics on every page greatly increases load time on subsequent page views.
3) High Value Perception.
The top 4 links at our site judiciously use words; Traffic, Free, & Special. These words are proven to draw interest and attract attention. The second part of this though is to actually deliver value. Nothing will turn people off faster than a phony. If you promise a FREE Report, then you'd better deliver it. This leads us to another point.