In the beginning you can only cook eggs. Just stick with it. Making harder food costs more items and is just as effective.
Cooking
If you cannot cook well, buy a microwave or a refrigerator and select 'Snack'. You can be full without having to cook repeatedly.
Extractor
When treating a pet that has swallowed something, you can extract the item from the belly to get a free item. The next day when the owner comes to pick up the pet you get will get money and an item.
Hilary Duff
If you treat Hilary Duff's pet well you will get more people to come over to you to treat their pets.
Increasing comfort and energy levels
To get your comfort and energy level up, go to the bed and select "Nap". If only your comfort level is low, sit on the couch or a chair.
Moving out
When buying a new house, your house will be in your inventory. If you want to move just "Use" it. You will be asked if you want to move out. Tap "Yes".
Pet in inventory
Open the cage that your pet is in, tap him, then select "Put in inventory".
Sicknesses
Broken leg
Length: 5 days
Cure: Put bandage on and let him or her rest a lot
Flea
Length: 3 days
Cure: Wash him or her with an anti-flea shampoo
Flu
Length: 3 days
Cure: Flu medicine for three days every day one time
Item swallowed
Length: Unknown; as long as it takes for you to extract it
Cure: Buy an Extractor and extract the item from the pet's belly
Ugly
Length: Unknown; as long as it takes for you to make the pet beautiful
Cure: Comb his or her hair and put some clothes on
Worms
Length: 3 days.
Cure: Feed him or her anti-worm food
Worms
If you have tried everything else and the only possibility that remains is worms, you can feed the pet anti worm food. You can save time if you feed him the anti-worm food immediately.
Cheap food...