Tai-otoshi is classified as a hand throw (te-waza) and keep that in mind as you do this technique. There should very little body contact. Use your hands to direct this throw.
For more te-waza visit the judo throws page.
Study this throw done in many ways by different competitors by watching this video compilation.
A more advanced version of this throw is the drop knee version. Get some tips from world champion, Neil Adams on how to do a drop knee tai-otoshi.Did you notice the unusual hand grip?
Use ouchi-gari to set up for this technique. Attack strongly with the ouchi-gari and attempt to throw uke backwards. As uke recovers their balance they will come forward. As they do turn in for your main waza.
If uke manages to avoid your tai-otoshi follow up with an uchi-mata.
Counter this waza using a Kosoto-gake or Kosoto-gari. Make sure you step off the attack first. When you have got off the throw, reverse the direction and counter backwards.
Practise your footwork with this drill. Your attacking let should not be too close to uke’s leg.
Lay two belts on the tatami in a cross. Uke stands on two of the belts as shown. Tori should aim to place both feet slightly in front of the belt.