MyBB Community Forums

can any one say me how to make site map

Well it depends on the way you want to create it. You can easily create a site map manually by using unordered lists:

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A site map can be generated dynamically of your forum, if that's what you mean?... although it will probably need a plugin to integrate into your forum.

There are also Google Sitemaps, which help your search ranking too - http://www.google.co.uk/webmasters/tour/tour4.html

if you mean a google sitemap (sitemap.xml) then take a look in the mods section - there is a plugin you can install

There is this one in the mod section http://mods.mybboard.net/view/sitemap-generator