How to get Youtube videos to work with firefox in Linux

In most cases, many have trouble viewing youtube videos with firefox when running linux(ubuntu).There could be many reasons for this, one common reason, is gnash interfering and not allowing flash to open the youtube video causing the problem.
Typically the youtube video screen is blank with nothing at all, so to get this fixed, you basically remove gnash and install flash on top of it.So here's how you go about doing it

Step 1 : Go to the Terminal(Applications->Accessories->Terminal) and do the following
Step 2 : Firstly,its better to remove flash incase its already installed, for this type sudo apt-get remove flashplugin-nonfree
Step 3 : Now remove Gnash by typing sudo apt-get remove gnash
Step 4 : Now install flash again by typing sudo apt-get install flashplugin-nonfree
Step 5 : Ensure that all firefox windows are closed and restart firefox
Step 6 : Now you should have youtube working!!