This is short walkthrough of Wordpress installation. This part is usefull if you install Wordpress theme for the first time. Before start, you must have a server that support PHP and enable access to MySQL databases.
After download wordpress, extract the file. And you will get folder named wordpress. Upload all file from those folder to your hosting server. You will need FTP credential and FTP Client for uploading wordpress. Contact your hosting for your site FTP credential and If you don't have ftp client, you can download it here.
After finish uploading wordpress, now try to access yor website URL from your browser. And you should see wordpress complaining cannot find wp-config.php. Click Create a Configuration File, and you will prompt that you need to know Database Name, Database Username, Database Password, Database Host, and Table Prefix. Click Let's Go to fill all detail of your wordpress installation.
And after all setup, you need to fill your site information (Site title, username, password, etc). But all of option can be changed latter. Bellow you can find image recap for wordpress installation
After you finish installation, you can login to admin page with username and password that you enter before. Point your browser url to http://yourdomain.com/wp-admin/
This is only short guide for installing wordpress. You can find more complete installation guide from wordpress itself by clicking this link