This is my first instructable, so as usual comments and suggestions are welcome.
Step 1: Gather Materials
You will also need the knowledge of a few useful knots, which i will be providing.
For more information on knots and lots of other useful knowledge join the Boy Scouts. Pictures of my Troop can be found here
Step 2: Sheet Bend
It is also very simple and safe, it will usually not slip (NOTE: I said "usually." don't expect it to support your weight. In fact, don't expect any knot to hold your weight unless it is a climbing knot, that's their job.) I was told that this knot was used by sailors to tie down sails with rope, hence the "Sheet" part of its name.
First take your larger rope and bend it (this is the "bend" of the sheet bend). In this case this is our webbing. Next slide the smaller rope up through the bend. this can be seen in the first picture.
Then, take the free end of the smaller rope and run it along the back side of the webbing, and then slide it under itself on the front side. this can be seen in the second picture.
Step 3: Two Half Hitches
Again, i apologize for the poor picture quality, i will do what i can to describe with words what is in the pictures.
With your smaller rope take whichever end is not attached to the webbing and feed it through your camera strap loop on your camera. Tie your everyday overhand knot (picture 1). With the end of the rope tie another. this can be seen in the second picture... sort of.
Step 4: Repeat 2&3
One thing that my friend recommended is to use electrical tape and tape a film canister onto the small rope part. This way you will have a place to store your next roll of film until you change, for those of us still using film, anyway. Great tip, Scott.
One final thing,make sure the knots wont slip or come undone once they get some weight on them. If you tied them correctly then I don't know why they would, but better safe than sorry. Just give the strap a few good, strong tugs to get the knots tight and settled and to make sure they wont slip. Once you are satisfied that you wont drop your camera then go out and enjoy.
As always, thank you for looking and please feel free to comment and give advice or criticism on my first instructable.