OK, low-whistle advice for newbies here. When I play my little tweedly-D whistles, I get a C# by uncovering all the holes, right? Now I’m wrestling with my wonderful Alba F, (my first low whistle), and I want to play an E. If I don’t cover SOMETHING the whistle falls from my grip and lands on my foot. Ouch!!! 
I can get the E by covering the bottom hole or two, and it sounds fine. It’s just awkward because I’ve never done it, I guess. Before I start training my muscle memory to do this…how do all you low-whistle players get the note below your 2nd octave root? 
Thumbrest - I use one from Susato.
Cover bottom hole, or use bottom pinky. If you cover the bottom hole, you need to learn to take it off when necessary. For example, several wider-bore whistles will break on the high a and b notes if you cover the bottom hole (xoo oox — that will work on thin-walled hi-D cheapies, no problem).
I cover the lowest hole for C# and use the pinky for notes that suffer from the lowest hole being covered. It’s just a matter of practise. 
By the way, Bloomfield, your avatar rocks. 
I wear my shoes to cover my toes.
Du weisst ja auch, wer das ist. Kennt hier in Amiland keiner.
Wie wahr, wie wahr…
Aber ist ja vielleicht sogar besser so? 
hundertpro.
Aren’t there any alternative fingerings for C#?
All whistles, all keys - I cover the bottom hole.
bottom hole or pinkie holding… that happens naturally each time differently.
While you are training your muscle memory invest in a pair of these:-
Covering the last hole should help. Try to get used to it. (It’s a damn fine whistle you got, by the way.)
Like suggested, use pinky or then cover the bottom hole. One useful thing to learn is also this fingering OOO XXX where you cover all the bottom three finger holes. It makes triplets (in this case D - E - F) much easier (the D fingering would be XOO XXX).
Grasp the bottom of the whistle with your toes. If you loose your grip, at least your feet are out of the way. 
I so rarely get to brag about any aspect of my whistle playing. But, as far as I can tell, the best thing about my whistle playing is that I never have any problem with dropping the whistle. I don’t do anything to hang on to the whistle other than keep it in my mouth and balance it on my thumbs.
Or, at least I don’t think I do. I’ll play in front of a mirror tonight.
Thanks, these were all good suggestions. What I ended up going with is a modifed harmonica rack that keeps the whistle attached to my face at all times. An added benefit is that I can also walk and run while playing, so I’ve started training for an upcoming marathon, as well. Necessity is the mother of invention. I think Frank Zappa said that.
If you’re into body modification you could go with a low whistle lip piercing.
Your whistle?
Let us know how the facial piercing comes out when you run into a wall. We’ll rename you Phineas (see the C&F main site). On the other hand, you’ll have a handy excuse for drinking only whiskey - any other liquid will gunk up the whistle too badly.