About the tablature
There is no recognized standard for how to write guitar tablature. I use an underscore (4_5) to indicate any ligado, either a hammer-on or a pull-off. I find it makes the tab easier to read than cluttering it up with the letters h (4h5) or p (5p4), and it's obvious which is meant. I use vertical lines for measures, and write time signatures outside the staff. Two lower case o's, placed vertically on the #3 and #4 strings, inside the staff, are a repeat sign. I use a zig-zag, vertical line at the left of a chord, to indicate a strum. All strums are down unless otherwise stated, or noted with the letters u or d above the staff. Chords tabbed without the zig-zag line are to be plucked or pinched, unless otherwise specified. If all chords in a section are to be strummed, I indicate that with a note, and leave out the zig-zag lines. Slow strums are tabbed note by note. Harmonics are indicated with an exclamation point: !12, double harmonics with two exclamation points: !!7. Double vertical lines indicate the end of the song.
Where the abundance of strummed chords makes the tab too busy for easy reading, I have employed several strategies. Sometimes, I write “All chords are strummed” at the beginning of the song. Where the same chord is strummed repeatedly, I may leave out the numbers, after the first strum, and use only the zig-zag lines. Spaces between notes do not usually indicate length of the note-- they are only added to allow the printed words to fit better. Except where the notes indicate a slow strum, I always allow at least one space (hyphen) between notes.
About the chords
Where possible, I include “standard” chord charts at the end of each song, with the chords in the order of their appearance in that song. Some tab artists write out chords like this:
C: x32010, meaning the sixth string is not played, the fifth string is fretted in the third space, etc. This takes a great deal less room than standard charts, but lacks the visual element, is confusing to beginners, and somewhat duplicates the chords as shown (vertically) in the tablature. I try to avoid such, but do use them occasionally.
I use a lot of barre chords. Selection of which voicing of a chord to use often brings out the melody. To distinguish voicings of the same chord, I use Roman numerals in smaller type after the chord name, to indicate the chord's position (where the barre goes.) For example, the C major chord is normally played without a bar, but is sometimes played as an A barred in the third space (A III), or an E barred in the eighth space (E VIII).