Today’s progression uses simple “rise and fall” dynamics (or ascend/descend, however you want to phrase it). It’s pretty self explanatory, so first take a listen…
So there’s an initial climb up to that F# V chord before collapsing down, eventually further than the point we started on the fretboard. By using an inversion of that tonic B major chord, rooted on the 3rd of the chord as opposed to the root note, we can bring the opening closer to the rest of the “climb”, giving the sequence more apparent cohesion. Sometimes you may want more disjointed movements, so it’s good to understand that distinction.
For the theory buffs out there, the second chord in the progression, E minor, is a good example of turning the IV chord into an iv – major into minor. It then loses the natural stability of the IV chord, allowing you to create a more tragic expression, which I’m sure you’ll agree is what was accomplished here!
The use of the open B string came in handy as well, as a “drone string”, giving yet more cohesion to the sequence.
Another thing to note is, when the progression descends from its peak F# major chord, the movement on the D string is chromatic, which is useful in giving the progression some intrinsic harmony. Try building chord tones around chromatic sequences, on any of the strings, and you’ll be surprised at how it can guide you through some intricate harmonies.
All this is food for thought of course, and there’ll be times when randomnly plonking your fingers at various places on the fretboard will yield epic results, but you should always be asking yourself “what more can I do with this?”