Place some sandy soil (crickets like to burrow into sand) in the aquarium.Step 2.)
Put the toilet paper roll or cardboard egg crate inside (they like to hide in it).Step 3.)
Keep one area of the soil moist everyday by spraying this area with water (preferably not just out of the tap...put some water in an open container for at least two days so that the chlorine can evaporate out of the water).Cover the aquarium:
This is where the crickets will lay their eggs.
You'll want to make sure the tank has a good lid, or you'll end up with thousands of bugs in your house. (ick!) Use a screen lid- the crickets need the ventilation, but be sure the holes aren't too big or the little bugs get out through them. I've seen commercial lids, and have also heard that metal mosquito screening secured with duct tape works well too. Note: don't use fiberglass or plastic--crickets WILL eat their way through this.Add crickets to their new home and voila! Cricket tank.
Feeding:
Feeding is easy. Crickets need a slice of orange to get moisture (they would drown in a water dish), they also eat small hunks of lettuce and a small pile of oatmeal. You will need to replace the orange slice and lettuce about twice a week.In a couple of months you will see very tiny ant-like creatures running around when you spray water in your moist area. You will not be able to make out the newly hatched crickets for some time, but with a magnifying glass they become visible.
You can also purchase some "gut load" at the pet store to fatten up your crickets for your frog. (This part is highly recommended for the health of your pet frog! This stuff adds extra needed vitamins to your frogs regular bug diet.)
Good luck with your crickets!
More details on cricket and bug care: