The quickest way fron Santiago de Chile to Puerto Natales?

What is the best way to get to Puerto Natales where I hook up with friends for Patagonia? I think I need a minimum of 3-4 days with busses. Does anybody has details? Also Easter Island may be on the agenda on the way back, when I have a bit more time. Any suggestions of how to get there, how long to stay, etc. highly appreciated. Thanks!