Well...I don't have a specific regimen.
I usually always have my bass on my lap whenever I am on TB(you figure out the time in that one
generally though I make a point to work in at least 10-20 minutes of solid shedding on a specific technique, or concept every time a sit down.
Like today for example, I spent about an hour total on double thumb(and double pluck)permutations and paradiddles
I also spent a good deal of time(about 30 minutes today) singing along while I play. I'll often do this in my warmup, which usually consists of running scales and chromatic exercises up and down the neck quickly. (and "river people" that's part of my warm-up)
Any given day, I'll spend at least 3-4 hours playing, out of that a good hour or so is solid practicing.
But I spend a lot of time just noodling and figuring out songs, and coming up with new ideas.
lately I've been using my metronome a lot more, since I've been getting into more technical exercises like permutations and things like that.
often I'll set the metronome somewhere and just groove on that click with the fewest notes possible, and try and keep it happening.
Also I usually spend a couple minutes on harmonics, going over chords and things, artificial, false all those.
and I try find time to have a little fun(speedy runs up and down the neck)
but as I said I don't have a strict regimen, some days I barely do any good stuff, other days I shed like a cat.
as far as stretching or anything...I don't really do any of that..I do some tendon exercises throughout the day though.
Oh yeah, I also practice piano during the day, learn chords, and I'm currently chugging through the real book for my reading.
And lately I've been doing solfege