you remove the oil injection hose that goes from the oil tank to the intake manifold (be sure to drain out all the shit first)
and then plug the 2 holes where the hose connected.
Start pre-mixing at your desired ratio (I prefer 50:1)....and go!
Simple people like to remove the oil tank from the under the seat too to make it storage space (extra spark plugs, tools, bottle of oil)
Thats up to you.
Also this has been covered a ton of times....please use the search button before making a thread on the forums. Chances are the topic have been discussed to the point of beating a dead horse.