You can use any human glucose meters. If you are in the US, the Walmart Relion brand meters are good and inexpensive to use. It is great that you want to hometest. Since your cat also is being treated for an infection and also you are no longer feeding dry food, it is very important that you start testing as soon as possible. The infection can raise glucose levels and as it is treated, the levels will begin to drop. Removing dry food from the diet also can cause a significant drop. By testing before every shot, you will know if it is safe to give insulin. In the US we recommend a reading of 200 for newbies to use as their "Don't Shoot" number. This means if it is 200 or less, skip the shot. By doing this, you avoid the risks of hypoglycemia.