When tackling a banjo tune you would like to add to your repertoire the first step is generally to learn the main banjo part from a trusted source (say a preferred recording or a solid written arrangement).
A second step might be to try something to make it your own. You could alter the original banjo part to your tastes and strengths (which is never a bad idea) and/or you could concoct an original second break.
The nice thing about an original second break is it allows you to build off a strong piece of music. Plus, you already know you like the first break so at least that part of the song will fly even if your original break crashes and burns.
For this example I came up with an original 2nd break for Scruggs' 'Ground Speed'.
The original melody is classic; a rip roaring descending pattern up the neck leading to the open strings and back again. Generally played at a good clip, though it also sounds good slow, this tune is freaking addictive.
For the A section of my break (in the video it begins when my left hand reaches around the 15Th fret) I decided to keep the melodic contour intact as much as possible just moving everything a little further up the neck. Then I threw in a long descending pull off lick as a way to get from up the neck to back down low. Does it work? You tell me, but that's what I did.
For the B section I keep close to the original save for the circus music quote. I find a more conservative B section balances the long chromatic-ish run at the end of the A section.
There are many approaches you can take to a 2nd break and I encourage everyone to try it out, have fun and come up with something different.
Here's Ground Speed(man do I look goofy when I play)...