You can plan a trip to Bhutan on your own. However, you will probably have a less stressful time before and during your vacation if you have a travel agent helping you sort out your documents and planning your itinerary. You can find a number of affordable Bhutan tour packages listed by trustworthy travel agents on Tripoto. I have attached a few below. Once you fill the form and the agent contacts you, you can discuss your concerns and decide if you want to go ahead with it. :) Hope this helped!