It's important to start by observing it from afar. A healthy mouse will be alert and cheerful. Because mice are nocturnal, you should visit the pet store at night when they're most active. Check the bottom of the cage for diarrhea, which is a sure sign of trouble.

Next, try to assess its character: it should calm down quickly in your hand and not try to escape or bite. Avoid buying a frightened or nervous mouse, which will be too difficult to tame.

Because mice are sociable animals, your mouse's cage should be placed in a busy part of the house. Avoid putting the cage near doors because of the potential for draughts.

And because mice are very active, yours will need plenty of space to keep in shape. It's even a good idea to provide a multi-level cage. The best way to line a cage is with wood shavings, but avoid cedar.

Bedding to avoid:

1. Hay or straw
2. Newspaper
3. Cat litter
4. Cracked corn or cob
5. Compressed recycled paper

Because mice tend to run away at every opportunity, it's vital that you provide a safe, escape-proof cage. However, if your little friend does slip out, here are a few tips to help you find it again:

1. Move furniture carefully to avoid injuring it.
2. Close all doors in the house to isolate your mouse.
3. Place a bowl of water and food in each room.
4. Once you've isolated it, place its favourite treat in a box; it won't be long until your furry friend comes out for a snack.

A few toy ideas:

1. Wooden ladder
2. Hanging rope
3. Wooden, leather or cotton rope toys designed for birds
4. Paper bags
5. Bird's nest
6. Old magazines or books
7. Cardboard boxes
8. Empty toilet paper or paper towel rolls

Because mice are nocturnal, they should be fed, and their water changed, in the evening. You should also know that coprophagia (eating of one's feces) is a normal behaviour of mice. Although it can be off-putting, coprophagia serves to recover B-complex vitamins and other nutrients that mice's digestive systems didn't have time to process the first time around.

As mice are very active, they burn the calories they ingest very quickly, so overfeeding is a non-issue. Rodent food should make up between 80% and 90% of their diet. You can complement that with fruits, vegetables, grains and cheese, which are the best treats you can give your little friend.

Recommended fruits and veggies include apples, asparagus, blueberries, broccoli, carrots, cauliflower, celery stalks, cherries, grapes, lettuce, melon, oranges, parsnips, papaya, peppers, pineapple, plums, pumpkin, radishes, spinach, strawberries, turnips and zucchini.

Grains: oats, Cheerios^®, Rice Krispies^®, Corn Flakes^®, rice, bread (ideally whole wheat or multigrain), croissants, muffins and couscous.

Things to avoid at all costs include sweet pastries, chocolate, and fruit seeds and pits. Fruits and vegetables can be given raw or cooked. Always provide your mouse with a little dry hay, which is an excellent source of natural fibre that helps digestion.

And always remember to provide fresh water.