A feather flip is a 1/2 impossible late anticasper flip, I know two ways to do this trick, you can start like you would for an impossible or you can start like you would for a pressure flip (the one looking like an inward flip, so it's a "backside toeside varial pressure flip" to be precise).
Animated gif (with an impossible start)
With an ollie impossible start:
1/ Put your feet like you would for an ollie impossible.
2/ Do an ollie impossible, try to make it wrap around your back foot and spin almost vertical.
3/ As soon as the board has reached 3/8 or 1/2 impossible and is upside down put your front foot on the graphics side (anywhere, I personnally put it on the bottom of the nose) and let the back foot under the board (it may slide a bit toward the tail, but I think you don't have to mind about that), this is the "anticasper stance" in midair.
4/ Raise your back foot up and forward and push with your front foot down and backward to induce the late anticasper flip, the board will spin vertical/fs. Lift your front foot as soon as the anticasper flip motion has started, it will help for the landing.
5/ Land.
With a pressure flip start:
1/ and 2/ do half a pressure flip to get the board upside down, the rest is the same, except you may lose back foot contact so you may have to think about puting your back under the board after the 1/2 pressure flip (which can look very good).
Tips:
-Be fast, you have to make it quick if you want to have the time to put your feet back on the grip before landing, the late anticasper flip should happen at the peak of the trick or even before.
-You can try this: think about a fast exagerated impossible then scissor kick the board.
-Shin guards can be useful when learnig this trick.
-This trick can becom very consistent, it's cool if you wish to do it in lines
Variations:
-You can do frontside feather flips which may be easier to learn than the regular version.
-You can also do bigspin feather flips which are a lot harder but look very good (in my opinion).
-If you want a challenge, you can also learn switch epsilon flips (or regular epsilon flips if you are good at nollie feather flips), they are (switch) varial 1/2 heelflip late casper flip, and can also be seen as (switch) ollie front foot feather flips.
Animated gif (with an impossible start)
With an ollie impossible start:
1/ Put your feet like you would for an ollie impossible.
2/ Do an ollie impossible, try to make it wrap around your back foot and spin almost vertical.
3/ As soon as the board has reached 3/8 or 1/2 impossible and is upside down put your front foot on the graphics side (anywhere, I personnally put it on the bottom of the nose) and let the back foot under the board (it may slide a bit toward the tail, but I think you don't have to mind about that), this is the "anticasper stance" in midair.
4/ Raise your back foot up and forward and push with your front foot down and backward to induce the late anticasper flip, the board will spin vertical/fs. Lift your front foot as soon as the anticasper flip motion has started, it will help for the landing.
5/ Land.
With a pressure flip start:
1/ and 2/ do half a pressure flip to get the board upside down, the rest is the same, except you may lose back foot contact so you may have to think about puting your back under the board after the 1/2 pressure flip (which can look very good).
Tips:
-Be fast, you have to make it quick if you want to have the time to put your feet back on the grip before landing, the late anticasper flip should happen at the peak of the trick or even before.
-You can try this: think about a fast exagerated impossible then scissor kick the board.
-Shin guards can be useful when learnig this trick.
-This trick can becom very consistent, it's cool if you wish to do it in lines
Variations:
-You can do frontside feather flips which may be easier to learn than the regular version.
-You can also do bigspin feather flips which are a lot harder but look very good (in my opinion).
-If you want a challenge, you can also learn switch epsilon flips (or regular epsilon flips if you are good at nollie feather flips), they are (switch) varial 1/2 heelflip late casper flip, and can also be seen as (switch) ollie front foot feather flips.
