1. Downloading the XAP zip file
Download the ZIP or TAR versions of the file from the XAP Apache site.
2. Unpacking to your web server document directory
Locate the document root for your web server. If you do not have a web server, you can download one for free from http://httpd.apache.org/. The document root for Apache web servers is indicated in the conf file with the DoccumentRoot variable, and is called htdocs by default. For IIS the document root is under INetPub\wwwroot.
Create a subdirectory under your document root and unpack the contents of the downloaded file into this subdirectory.
For more information consult the documentation of your web server.
3. Running the initial example
Open up your web browser and navigate to this directory. You can typically do this using http://localhost. Locate ajax-index.html and run in your browser.