The most basic thing you need to keep your cat safe is the glucose testing., somehow, someway.
If you can do that with blood tests, that's fantastic, as it really helps ensure you don't give insulin when the cat is too low to get it, and that you can determine how your cat responds to it throughout the day with midpoint testing (when you can) and curves (when needed for the vet ). Those last 2 determine dosing when you follow the tight regulation protocol and may be done frequently. Also, if you can do a curve at home, it may save you money by not having to go to the vet for a fructosamine test to see what the average glucose levels have been, as you will have collected them and can provide them to the vet.
If blood testing isn't an option yet, you have to go by other, indirect methods, which aren't as accurate, and in the case of urine glucose testing, it reflects the cat's state over the period the urine was accumulating (typically a few hours, but depends on the cat).
Because of the lag in urine glucose tests, you might want to make a list of the signs and symptoms that indicate a hypoglycemic attack and use them as a monitoring checklist. Hypoglycemia kills quickly.
A hyperglycemia list has all the symptoms of diabetes on it - excessive hunger, excessive thirst, copious urination, etc. Hyperglycemia can lead to potentially fatal ketoacidosis. When you observe reductions in these symptoms, you are making progress in managing the diabetes.
You might find it useful to view this summary article by Dr Rand, a feline diabetes expert:
http://www.uq.edu.au/ccah/docs/diabetesinfo/link3.pdf Most importantly, look at the last 5 lines of the table - what to do if glucose measurements aren't available.