If you have set up a web hosting account, installing Joomla includes four tasks:
Check with your web hosting provider to make sure that your hosting is technically eligible for Joomla version you are planning to install. Always try to install latest version of Joomla for more secure and feature-rich website.
Download the latest version of Joomla Full Package (and not upgrade package).
Use cPanel file manager or FTP client to upload downloaded zip file to your web hosting directory you wish to install Joomla.
You can perform this step in parallel with the above step 3. While your Joomla package is uploading, you can work with your database. This has three sub-steps:
Extract the zip file that you have uploaded in the step 3.
Open your website directory where you have extracted Joomla files in any browser (Google chrome recommended). You will see the beginning of your Joomla installation.
Configuration: Fill in all relevant details (You can change these later also) - site name, admin email, username and password. Make the site offline. Then, click Next.
Database: Use the details from the step 4 above to fill username, password and database name. Then, click Next. This password is not required anymore.
Finalisation: Nothing much to be done here. You can choose to install sample data, but it is not required and I don't recommend it. Just click Install. You will see following message:
Congratulations! Joomla! is now installed
Click on Remove installation folder. This is important for security purpose. Also, delete the zip file you uploaded in the step 3.
Simple! You have just finished installing Joomla. Now you can login to your administrator panel using log in details created in step 3.