That's exactly what I mean but don't know how much insulin to increase per amount of carbs
General starting guide is about 12g carbs to 1unit. 12g:1u. Try that, and then change the dosing according to sensitivity.
Sometimes you'll find yourself more sensitive towards insulin and vice versa. But you'll eventually learn your traits.
I hadn't done a finger prick for around 7 months...Then yesterday my concerned brother wanted to know if I'm in control or not, 4.4mmol
My point is it takes time, but if you learn your ratios, your trends, you can get to the point where you don't test (not recommended or suggested by me, what I do is off my own volition and I understand the risks associated with).