I've been making my first attempts at writing some pieces for solo guitar, and I'm wondering how best to make use of finger and position markings when putting together a final score. I've looked over some guitar pieces and there seems to be a fair bit of variation in terms of how specifically and explicitly things like fingerings and positions are notated. I understand that the overarching goal is efficient communication of the musical idea but I'm wondering if there are any conventions or best practices that I should always be following.
Some specific questions:
1. Is it ever mandatory to include plucking-hand indications (I.e. p, i,m and a)?
I've yet to find a place where these feel useful, and they mostly seem like they add extra clutter. Should these simply be reserved for especially intricate passages or should they be used more liberally?
2. How many fretting-hand markers (if any) are generally expected?
I've found these slightly more useful, but I tend to limit them to situations where a) an open string should be played or b) two adjacent notes are played with the same finger, thus indication a shift in hand position. Is this good and are there any other cases in which you'd expect to see fingering indicated?
3. When and how should I use position markers?
When it comes to indicating position on the fretboard I've seen three different approaches:
a) Simply leaves it up to the performer b) indicates position with a lone roman numeral while c) also adds a line to more explicitly mark which notes are intended. I'm personally leaning towards b) as the cleanest option. I know that c) is often used to indicate a barre (in which case the numeral is preceded by B or C), but I'm not sure which is preferred otherwise.
More general tips would also be appreciated if there's anything important I've not asked about.