1) Let's focus on the glide into the turn first:
When you start your glide, you should be slowly submerging yourself underwater, so you do not start your flip turn with your head and back out of the water.
This drill is called The Submarine.
To practice this, swim freestyle to the wall as normal, and 1 meter or so before you are ready to flip, start slowly submerging your upper body at a very low angle.
Your head and back should be slightly under the surface.
Once you get right below the surface with your upper body then initiate your flip.
If this drill is mastered perfectly, you will feel how your legs flip totally on their own at a higher speed than normal.
2) the Second tip would be the positioning of the feet on the wall:
Many swimmers think that they have to flip their feet as fast as possible in order for the turn to be fast.
While this is true, it is easily interpreted in the wrong way. It usually causes the legs to be straighter and a huge splash by the wall.
That is a big NO-NO.
The motion of the feet is smooth and there shall be no splash on the pool deck from your turn.
In order to have a fast flip, you will have to remember one rule.
Smaller object moves faster than a larger one.
Hence, it is very important that you keep your legs bent (not straight) - as small as possible on the way through the air.
When your feet reach the wall, they are basically almost in the level below your butt.
In other words, your heels create a beautiful hole in the water for the rest of your feet to follow and no splash is created.
Not too close and not too far from your buttocks. Just an optimal distance, so your push-off is as strong as possible.
If they are too close, then you will sit on the wall forever before you are able to push off.
If they are too far, then your push will be very weak.
You can think of it as having close to a 90-degree angle at your knees.
I don't have a real practice trick for this, except maybe trying the flip on the wall, where there is a dry spot on the deck, and try not to get the pool deck wet :)
The feet should also not be very close together when hitting the wall.
Usually, about one foot apart or so is a good practice.
3) The Last tip would be the breakout:
When you push off the wall and are rotated back to your stomach, your streamline should be perfect as this is the time when you go the fastest in the pool.
You still carry the momentum from the wall, so by minimizing drag, you increase the distance traveled at this pace.
The important thing to remember is that if you are too deep or too shallow, you do not go the fastest as there is some turbulence from the bottom or from the surface of the water.
You will need to find the optimal depth for your breakouts (I'd suggest starting at about 80 cm or a couple of feet).
Ok, now the trick comes into play.
Once you start feeling yourself slowing down a little.
The only thing you need to do is to add a couple of little snappy dolphin kicks (or more) right before you surface.
This will give you the final burst of speed and will make your breakout a success.
The breakout itself is for another post, however, keep in mind - head is down, no breath on the first pull, and no jumping out of the water - keep it smooth, right at the surface.