First, make sure “quantize to frames” is on (it should always be on when cutting video).
Bring focus to the tracks by clicking in that area or hitting alt-0 (that’s a zero).
Zoom in using the mouse scroll wheel or up arrow.
Watch the TC reader and hit your left and right arrow keys and see if they are advancing by frame. When you’ve zoomed in enough they will, and you can edit with frame accuracy.
What looks like a 3-step process is actually extremely quick and almost subconcious as you get more familiar with cutting in this way. I find myself zooming the track view in and out constantly for different purposes.