Use the effect of addition of vibrato to a note sparingly. Sound must stay the same when using the tongue. Keep enough breath support to keep tongue moving. Top lip too tight will cause a whistle in the sound. Open teeth more for fast tongue.
Every note has a life of it's own.
A short note is always preceded by a shortened note. Use Unfinished Sym. for develpoing tone color. Reach for the flute and then bring it to you. Players duty is to present what the composer has written - not what you think he has written. Lock teeth and move lips to demonstrate flexibility.