Second, rummage around the house for "little treasures" so put in your bottle.
I collected rings, shells, beads, marbles, cars, pins, locks, keys amongst other things.
Third, put about 10 treasures in your bottle. I wrote down what I put in the bottle and taped the paper to the outside.
Fourth, fill the bottle halfway with salt/rice/birdseed/whatever. I used salt. And a funnel.
Fifth, glue the lid on. Trust me on this one.
PLEASE NOTE: If your bottle isnt COMPLETELY DRY, it'll look like this big clumpy mess!