I made this last year to display some of my favourite photos I've taken of the kids :) It's easy peasy!
You'll need: An old empty frame (the bigger the better!), drawing pins/thumb tacks, string or thread, tiny pegs and a bunch of your favourite photos printed out.
Step 1: Paint up your frame if needed. I found mine dumped in the street, it was plain wood and pretty bent up and had water damage! BUT it was huge so I ignored all that..
Step 2: Lay the frame wrong-way-up on the floor to attatch the threads to the back with tacks (tie knots and pin through the knots). This requires a bit of experimenting to see how many rows you want, depending on the size of your frames and photos. Make sure the threads are pulled tight across the frame as once you hang pics the weight will make them drop slightly.
Step 3: Hang your frame up on the wall (mine took 4 nails to balance it on and one big fat nail at the bottom corner to hold the bent up part flat to the wall... you shouldn't have this problem if don't use a dodgy frame) and peg your pics on, messing around with placement until your eyes are happy. Job done!