Before you get your gerbils, you should have a home ready. An aquarium is ideal, and a wire lid is NECESSARY. Always make sure you have a wire mesh lid to cover it because gerbils can jump! Never just assume they can't jump that high--they can.
There are other options out there, such as wire cages and plastic Habitrail homes. I don't recommend either of these. Wire cages are often gnawed on incessantly by gerbils, which can be both annoying and harmful to them. They can lose fur on their nose and get rust stains on their coat. They will also kick bedding out of the bars, making a huge mess. As for the plastic setups, these have poor ventilation and smell rather quickly. Additionally, they are easy to escape and easily gnawed to ruins.
In your gerbils' home, you'll want to include some toys. For example, wooden houses, toys full of holes, and wheels. Some people feel wire wheels pose the hazard of gerbils' tails getting caught but i can't ever say I have had this trouble myself. I stick to using plastic ones. You can also include cardboard boxes and tubes in your gerbils' home for them to gnaw on and make a nice nest out of.
The tank pictured below is perfect for a gerbil. Fill it up with a fair bit of sawdust and your gerbil can burrow forever.
