In addition to Aaron's answer, another option is to use the base-shortest-duration
property as discussed in the documentation here.
This property basically uses a note duration as its unit of measurement, so #(ly:make-moment 1/16)
will use a sixteenth note, #(ly:make-moment 1/8)
will use an eighth, etc. (Although you can use any fraction, not just fractions that suggest clear note values.) This means that the smaller the number (like 1/16
as opposed to 1/8
), the more spaced out the score will be.
\version "2.20.0"
\score{
\relative c' {
c d e f g a b c
}
\layout{
\context {
\Score
\override SpacingSpanner.base-shortest-duration = #(ly:make-moment 1/16)
}
}
}

And for anyone that doesn't know LilyPond but it interested in learning it, I highly recommend the YouTube tutorial series by soundsfromsound.