Hi,
I would change the 'could' to 'should' in Copepod's post, if your using insulin you need to test before you go to bed, when you wake up and before you eat, this as a minimum. Then if your exercising, driving, feeling unwell or feel you have high or low blood sugar aswell.
Saying that, it is easy to forget. Especially if you've fallen out of touch with regular testing, you could set alarms on your phone, or some meter's have settings to remind you for this very reason! (my meter reminds me to change my infusion set!)
Make sure you use all 3 fingers on each hand (not thumb or index finger), use both sides too, using the tip of the finger. try avoid the middle and very top as i personally find this can make your fingers sore and quite thick skinned. I test around 8 times a day average and my fingers are completely fine. Also having poor control (swinging high and low) isn't going to hlp your healing abilities. You may find as you get back into testing regularly that your control will improve and your fingers will heal better and faster, helping with the thick skinned feel to your fingers.
Hope you get back into the swing of things, i know it's hard to remember at first.
Good luck and all the best x