I wrote this message to the FLUTE list in answer to someone who wanted help getting to this note.
I learned another tip from Robert Dick lo these many years ago that you should think of moving that particular digit from muscles in your _back_ not just the finger itself (I think this relates to a Tai Chi approach where one tries to use the largest muscle group to obtain a specific movement).
Dear departed Fred (Prof) Schroeder, my undergrad flute professor, also had a good exercise:
Using a "and four and one - two - three" rhythm at about 1/4 note=60 or so, play first octave notes, slurred, as follows:
G-F#-G F natural
G-F#-G E natural
G-F#-G E flat
G-F#-G D natural
and so forth until reaching the low C (or B). The goal is to get the clarity of tone you have on the G down into the swampy lowlands, as I like to call them. The goal is to have as clear and focused a sound on the lower notes as you do on the first three as well as having as smooth a legato as possible between the slurred pitches.
Although some disagree with the following, I think it's good practice to begin scale practice with the lowest note in the scale that is on the flute (i.e. C1 or B . . what? minus one?) so we get used to "jumping in at the deep end" and have less difficulty when asked to do this in a piece.
The already mentioned by others advice to get the fifth finger to "assume the position" (as it were, if you will, and why not?) beforehand on the notes that use the footjoint keys is also good. In other words, raise it on the first F# of the playing low c exercise and place it on the C#, C, or B keys on the second G in preparation for the slur to those notes.
HTH.
JR
John Ranck
ranck@fas.harvard.edu