First Download Portable Version of XAMPP From here
Once you have downloaded the XAMPP portable file. Run the installer, and click Browse choose where to install your server… You need to click on the folder icon, and then select your USB drive.
Click on next to continue the installation. The installer will now install XAMPP on your USB drive. Using your portable server is very simple. Open the xampp folder on your flash drive and launch xampp-control.exe.
Click Start beside Apache and MySql to get your webserver running.
Now you can view it by browsing to //localhost/xampp or //127.0.0.1/xampp in your browser.
Now choose your default language
Now click on phpMyAdmin tab
In phpMyAdmin Click on the Databases on the top menu bar, enter a name for your database in the “Create new database” box, and click Create.
Now download WordPress to your computer. Extract the downloaded .zip file to your Desktop and open it.
Now save all of your web files in the \xampplight\htdocs\ folder on your flash drive
Once you have copied WordPress files, you can run the WordPress installation by accessing your site at //localhost/newsite in a web browser
Click Create a Configuration File to continue.
Enter your WordPress database name, username (In the username field you need to enter root) and password, leave the other two entries as default, and click Submit.
Enter a title, username, and password for your test blog, as well as your email address, and then click “Install WordPress”
Click “Log In” to access your WordPress admin page. Enter your username and password, and click Log In