Assuming you aren't drastically leaving the race line (I.e. not straying more than a foot)
I think of it as a fairly simple approach, with a question
where do I want to get on the throttle?
There are really 3 different kinds of corners here, the third being neutral corners. Corners that can go either way. I almost always treat these the same as exit corners as more drive helps to lower lap times
So, an "Entry Corner" is one where you intend to get on the throttle late or, depending on the way the track goes, not at all. This is a corner where you intend to carry speed into the corner but not necessarily increase speed mid-late corner.
An "Exit Corner" is one where you intend to get on the throttle early to set up for getting a good drive. This is a more traditional approach, to get the bike slowed and set up to ride the rear wheel out of the corner.
I like the way Ken Hill phrases it as well, it's all about the proportion of the deceleration zone to the acceleration zone. An "Entry corner" is one where the deceleration zone is longer than the acceleration zone. While an "Exit corner" is one where the deceleration zone is shorter than the acceleration zone.
https://soundcloud.com/ken-hill-5347...s-exit-corners
https://soundcloud.com/ken-hill-5347...-entry-corners