There are two ways you can upload to a server .
File transfer through browser & FTP

~ File transfer through browser
- Go to the Control panel your webhost has Given you. Select file transfer for uploading & managing files.
Now the File transfer through browser is pretty odd for managing files .

~ FTP ~ (You got to have a FTP supported host)

1 . You Need a FTP program for this , I prefer SmartFTP

2. After Downloading Install the program Intall it .

3. Now put the server name / username / password , your host gave you

4. Enter

5. You`ll see many folder`s. Usually it`s the public_html or www or maybe your subdomain name .

6. Now just drag and drop the files you want . :)