You would want to set up a hallway page that links to your main page and all your doorway pages. You can then put all these pages in a directory so you would have
www.whatever.com/directory/hallway.html and then
www.whatever.com/directory/doorway1.html ,
www.whatever.com/directory/doorway2.html, etc.
Use each doorway page to target one keyword phrase that is related to your main page. So if your page is about amateurs, one doorway could target "asian amateurs", another "amateur teens". etc.
For a simple formula you can have approximately 200 words of text on each doorway page with your keyword phrase appearing anywhere between 5 and 10 times. If you want you can even link all your doorway pages plus your main page and your hallway page from each doorway page. You can do this by using 1 X 1 transparent gifs. This will increase your link popularity plus an SE spider will pick up all your pages just by spidering one. But you still want to submit your main page, your hallway page and your doorway pages to the SEs individually since you don't want to rely on the spiders.
Also, if your main goal (and I assume it is ) is to get traffic to your main page, you want to place the link to your main page as high up on the doorway page as possible - preferable right after the body tag.
Finally, in the URL for each doorway page, place your keyword phrase so for example, the URL of the page targeting "asian amateurs" would be
www.whatever.com/directory/asian_amateurs.html - this will help you out in the search engines that give credit to keyword phrases appearing in the URL.