Measure twice; cut one, two, three, four times or more. ;-) Then, of course, it will probably still be too short!
Practice . . . practice . . . practice . . .
I have the same problem and I’m too old to ever “get it.” I like to blame it on my cheap tools, but vision is also a good excuse!
L/W
“Those who would give up essential Liberty, to purchase a little temporary Safety, deserve neither Liberty nor Safety.” Benjamin Franklin