Well if it's your place and a perminent situation the best thing you can do really is to board up the windows however if you want something easier to remove or if it's not your place Panda Film is probably the best stuff available to you.

 Just messure up the area you want to cover , adding a little to all sides so that you have something solid sticking to the wall and you have something to put your tape to  , and proceed to tape it up with cloth-tape . I have found the cloth tape to be best as PVC Gaffa tends to come unstuck under the weight within a few days where as cloth tape is made to hold a bit of weight and also sticks to both smooth and rough surfaces . Below is an image of a roll of cloth tape so you know what to look for , Panda film can be found at any hydro shop

Once the panda is up you should have a completely light proofed window so that no-one can see what you are up to

Tutorial written by Pure for cannanation.com/ozstoners.com