Enter into the cPanel for creating FTP account. After entering on it, click on the FTP Accounts icon which remains in the files.
A page will appear as below.
In the above picture
In the box of a password, you give your password, and in the box of password (again), you give your password again.
Strength defines that how strong of your given password is. The strength of your password depends on the length of your password.
The directory is the home of the user and this user uploads which information is stored in the directory.
Quota defines that the maximum megabyte of information you can upload.
After filing these boxes, you click on the Create a new account.
If you watch just like the above picture, then your account has successfully submitted.